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HIGH SCHOOL SCIENCE TODAY

Textbook

THIRD YEAR

HIGH SCHOOL SCIENCE TODAY THIRD YEAR

Textbook

Philippine Copyright 2009 by DIWA LEARNING SYSTEMS INCAll rights reserved. Printed in the Philippines

Editorial, design, and layout by University Press of First Asia

No part of this publication may be reproduced or transmitted in any form or by any means electronic or mechanical, including photocopying, recording, or any information storage and retrieval systems, without permission in writing from the copyright owner.

Exclusively distributed byDIWA LEARNING SYSTEMS INC4/F SEDCCO 1 Bldg.120 Thailand corner Legazpi StreetsLegaspi Village, 1229 Makati City, PhilippinesTel. No.: (632) 893-8501 * Fax: (632) 817-8700

ISBN 978-971-46-0101-7

REVIEWER

Evelyn L. Josue has a bachelor’s degree in Chemical Engineering from the University of Santo Tomas and master’s degree in Teaching Chemistry from the University of the Philippines–Diliman. She has earned a diploma in Education major in Curriculum Development from the Deakin University in Melbourne, Australia and a diploma in Education on Research and Instruction from Hiroshima University, Hiroshima, Japan. She is a science education specialist IV at the University of the Philippines–National Institute for Science and Mathematics Education Development.

PREFACE

Discoveries in science and technology in recent years have had a profound impact on our society. We are now able to communicate easier with the use of the Internet and cellular phones. We have found ways to replace damaged body parts through prostheses and organ transplants. People are continually developing new medicines to treat diseases that were once fatal. Scientists have been able to clone animals, find alternative fuel sources, explore the far reaches of outer space, and develop better materials for construction. Even the way we entertain ourselves has been affected by discoveries in science.

With all these fascinating discoveries, it is important that you understand the scientific principles behind such advancements. The High School Science Today series has been developed with two objectives in mind: to explain key scientific concepts clearly and accurately within a context of unifying themes; and to introduce you to the technology and research techniques which have resulted from the application of these scientific concepts.

The topics in each textbook are organized to keep key science concepts in clear view. In each chapter, you will find discussions on specific technological breakthroughs and the implications these developments have on our global community.

Understanding science requires that you observe the things around you, perform experiments to solve problems, and explain the reasons for your observation. Each textbook contains activities that will help you develop the skills necessary in learning science concepts meaningfully. These activities will provide you with hands-on learning experiences. You will be asked to predict, hypothesize, describe, make models, form conclusions, calculate, and measure with accuracy and precision.

As such, High School Science Today will enable you to keep pace with the ever-evolving world of science and technology. We invite you to take this journey with us—into the future and beyond.

TABLE OF CONTENTS

UNIT 1 INTRODUCTION TO CHEMISTRY Chapter 1 Chemistry, Technology, and Society 1.1 Your Daily Life with Chemistry ........................................................................... 2 1.2 Chemistry in Industries and Technology ........................................................... 41.3 Contributions of Chemistry to Other Fields of Science .................................... 111.4 Branches of Chemistry and Their Applications .................................................. 141.5 Chemical Research Studies in the Philippines .................................................... 161.6 Outstanding Filipino and Foreign Chemists ...................................................... 171.7 Careers in Chemistry ........................................................................................... 20Chapter 2 Common Laboratory Apparatus, Equipment, and Techniques 2.1 Glassware Used in Chemistry Laboratory .......................................................... 232.2 Other Types of Laboratory Equipment .............................................................. 27Chapter 3 Measurement 3.1 Precision and Accuracy (Significant Figures) ..................................................... 363.2 Scientific Notation ............................................................................................... 413.3 Conversion of Units of Measurement ................................................................. 433.4 Measurement of Volume and Density ................................................................ 493.5 Measurement of Temperature ............................................................................. 50

UNIT 2 MATTER Chapter 4 Composition of Matter 4.1 States of Matter ................................................................................................... 564.2 Pure Substances and Mixtures ............................................................................ 584.3 Types of Mixtures ................................................................................................ 594.4 Elements and Compounds .................................................................................. 624.5 Metals, Nonmetals, and Metalloids .................................................................... 644.6 Classification of Compounds ............................................................................... 67 4.7 Acids, Bases, and Salts ......................................................................................... 694.8 Separation Methods for Mixtures ....................................................................... 73

UNIT 3 NATURE OF SOLUTIONS Chapter 5 Solutions and Their Properties 5.1 Characteristics of a Solution ............................................................................... 805.2 Process Involved in a Solution ............................................................................ 825.3 Solubility and Strength of a Solution ................................................................. 845.4 Factors Affecting Solubility and Rate of Dissolution ......................................... 855.5 Colligative Properties of a Solution .................................................................... 875.6 Concentration of Solutions ................................................................................. 935.7 Applications of Solutions .................................................................................... 98

UNIT 4 COLLOIDS Chapter 6 Colloids and Their Properties 6.1 Components and Classification of Colloids ........................................................ 1046.2 Properties of Colloids .......................................................................................... 1096.3 Colloids in Living and Nonliving Things ............................................................. 1136.4 Colloids in Food and Industrial Processes .......................................................... 115

UNIT 5 GAS: A STATE OF MATTER Chapter 7 The Gaseous State and Its Behavior 7.1 General Properties of Gases ................................................................................ 1227.2 Kinetic Molecular Theory .................................................................................... 1277.3 Boyle’s Law ........................................................................................................... 1307.4 Charles’s Law ........................................................................................................ 1337.5 Guy-Lussac’s Law ................................................................................................. 1367.6 Combined Gas Law .............................................................................................. 1377.7 Other Laws on Gas Behavior ............................................................................... 1387.8 Diffusion ............................................................................................................... 1477.9 Phases and Interactions ....................................................................................... 150Chapter 8 Gases and Their Importance 8.1 Some Useful Gases ............................................................................................... 1538.2 Safety Cautions in Handling Gases ..................................................................... 1568.3 Applications of Gas Laws ..................................................................................... 1588.4 Gas-related Pollution ........................................................................................... 159

UNIT 6 THE BASIC UNIT OF MATTER Chapter 9 Atoms 9.1 Development of the Atomic Theory .................................................................... 1669.2 Fundamental Particles of an Atom ..................................................................... 1729.3 Atomic Model ....................................................................................................... 1749.4 More on Protons, Neutrons, and Electrons ........................................................ 1769.5 Radioisotopes and Their Applications ................................................................ 1819.6 Energy Levels ....................................................................................................... 1849.7 Spectrum Analysis ............................................................................................... 187

UNIT 7 THE ELEMENTS Chapter 10 Periodic Trends of Elements 10.1 Origin of Chemical Symbols ................................................................................ 19410.2 Development of the Periodic Table ..................................................................... 19610.3 Periodicity and the Chemical Behavior of Elements .......................................... 19910.4 Periodicity and Properties of Elements .............................................................. 20710.5 Electronic Configuration and Distribution ........................................................ 21110.6 Elemental Groups in the Periodic Table ............................................................. 21610.7 Elements and Their Uses ..................................................................................... 229

UNIT 8 CHEMICAL BONDS Chapter 11 Nature of Chemical Bonds 11.1 The Bonding Process ............................................................................................ 23811.2 Bond Types ........................................................................................................... 240

11.3 Chemical Formula Writing .................................................................................. 24511.4 Chemical Bonds, Material Properties, and Uses of Substances ........................ 25111.5 Intermolecular Forces of Attraction ................................................................... 252

UNIT 9 CHANGES IN MATTER Chapter 12 Applications of the Changes in Matter 12.1 Types of Changes in Matter ................................................................................ 25812.2 Importance of Changes in Matter ....................................................................... 26112.3 Composition of Chemical Equations .................................................................. 26312.4 Types of Chemical Reactions ............................................................................... 266 Chapter 13 Chemical Equations 13.1 Mole Concept ....................................................................................................... 27413.2 Law of Definite Composition .............................................................................. 27713.3 Stoichiometry ....................................................................................................... 280

UNIT 10 MATTER AND THERMODYNAMICS Chapter 14 Matter and Energy 14.1 Exothermic Reaction vs. Endothermic Reaction ................................................ 28814.2 Law of Conservation of Energy ........................................................................... 29014.3 Factors Affecting Rates of Reaction .................................................................... 29214.4 Applications of Energy in Matter ........................................................................ 300

UNIT 11 ORGANIC AND BIOLOGICAL CHEMISTRY Chapter 15 Carbon Compounds 15.1 The Element Carbon ............................................................................................ 30615.2 Hydrocarbons ....................................................................................................... 30815.3 Hydrocarbon Derivatives ..................................................................................... 312 Chapter 16 Carbon Compounds and Their Uses 16.1 Some Biologically Important Carbon Compounds ............................................ 31616.2 Industrial and Agricultural Technologies Using Organic Compounds ............. 31916.3 Organic Fuels and Their Effects on the Environment ........................................ 327

UNIT 12 MORE ON BIOCHEMISTRY Chapter 17 Biochemical Substances 17.1 More on Carbohydrates ....................................................................................... 33417.2 More on Lipids ..................................................................................................... 33817.3 More on Proteins ................................................................................................. 34017.4 Nucleic Acids ........................................................................................................ 343 Chapter 18 Chemistry and Health 18.1 Food and Nutrition .............................................................................................. 34918.2 Food Preservatives and Additives ....................................................................... 351

Glossary 357Bibliography 360Index 361

INTRODUCTION TOCHEMISTRY

Unit1

Have you ever asked yourself what makes a particular brand of soft drink taste better than another brand? Or have you ever wondered why serious diseases, such as tuberculosis and leprosy, can be readily cured these days? Everything in this world deals with one of the important fields of science, that is, chemistry. Chemistry answers questions such as: “What are materials made of? How are the molecules of a material arranged in different phases? How do the properties of the material change?”

This unit invites you to take a closer look at this branch of science. You will learn how chemistry affects the lives of people and the world they live in and how it is applied in other fields of science, such as biology and physics. This unit will also teach you how to apply the scientific method in the study of chemistry.

Chapter 1

Chemistry is a branch of science that deals with the properties, structure, and composition of matter and the changes it undergoes. Its scope covers all materials found in our environment, whether natural or synthetic.

The study of chemistry began in ancient Egypt and Greece, where people prepared chemical compounds for medicine, perfumes, and cosmetics. During the medieval times, some people became obsessed with the idea of converting ordinary basic metals to gold. These people came to be known as alchemists and their craft as alchemy. The alchemists never succeeded in their goal. However, they discovered new tools and ways of working with chemicals and preparing new compounds. It is from their work that modern chemistry developed.

CHEMISTRY, TECHNOLOGY, AND SOCIETY

1.1 YOUR DAILY LIFE WITH CHEMISTRY

Fig. 1.1 The process of respiration

Many of the processes and changes you encounter every day involve chemistry. Chemistry is concerned with the different processes that occur in the human body. The food you take in consists of different chemical substances that your body needs. The process of digesting food involves the use of chemicals such as acids. Chemistry helps in maintaining proper blood flow, respiration, and all the other processes that take place in the human body.

High School Science Today III2

Introduction to Chemistry 3

Materialspen, notepad

Procedure1. Make a list of your daily activities (e.g., exercising, eating, and cooking).2. Tabulate the chemical processes and substances involved in each activity.

DATA TABLE 1.1Activity Chemical Processes Involved Chemical Substances Involved

Eating Breakdown of food particles into simpler substances (digestion)

Food, digestive enzymes, water

3. Present your table to the class. Discuss how each chemical process you listed affects your life.

QuestionWhat is the value of knowing the chemical principles involved in your various activities?

ACTIVITY 1.1 Chemistry in Daily Life

Your body is a living chemical factory. The food you eat is broken down into nutrients that your body needs. These nutrients are carried by your blood and distributed to the various organs, tissues, and cells of your body. In the cells, the nutrients are used to build new living materials and to produce energy for your various activities.

As the human population continues to grow, there is a need to build more homes. Builders use weather-resistant construction materials such as alloys. Alloys are homogeneous mixtures of two or more elements, one of which is a metal. These materials, which are more durable and cost-effective, are used to construct houses.

The medicine and health care items you see in a drugstore are products of chemistry. Drug manufacturers apply chemistry principles to produce them.

Activity 1.1 will help you identify the chemical principles involved in your daily activities.


Chemistry is very much a part of the modern world. Our society has been greatly influenced by technology. New materials are produced as a result of advances in the study of the structure and composition of materials. New types of equipment have also been invented to help the study of chemistry.

Chemistry has played an important part in the development of new materials. It has helped produce fabrics with properties and characteristics suited to people’s needs and conditions. The clothes you wear consist of materials taken from plant fibers or animal skin. Examples of these fibers are cotton, piña, abaca, silk, wool, and natural leather. Other fabrics are synthetic or man-made, such as rayon and nylon.

Chemistry has also contributed much to the fields of engineering and manufacturing. Cements, paints, glass, and iron nails are some of the products of chemistry in these areas. Some of these products are derived from minerals and rocks. Newly discovered and invented construction materials help in building structures that meet the demands of the present.

For example, in the construction of buildings, products such as iron and steel, cement, ceramics, marble, glass and fiberglass, plastic and Formica, wood, and fiberboard serve various purposes. The individual structures and properties of the materials out of which they are made were carefully studied to suit the purpose that the makers had in mind.

However, there are instances when scientific discoveries arise by accident. These accidental discoveries are instances of serendipity in chemistry. An example is the discovery of Teflon. This waxy, opaque material is used in making machine parts and nonstick cookware.

Artificial Flavors in Food

Did you know that the flavor of any substance is determined by the complex combination of chemicals? Coffee, for instance, has 800 different substances that produce its distinctive taste. Drinking it hot stimulates the nerves in your tongue and nose, enabling you to identify the flavor compounds present in it. Basically, scientists liquefy food samples and analyze these in a machine called chromatograph to determine what chemical components produce their respective flavors.

How are flavored substances made? One way is by concentrating extracts, for example, by boiling maple sap to make maple syrup. Another way is by isolating naturally occurring chemicals from plants, such as extracting menthol from mint. These flavors are called “natural” since they are derived from living things. However, chemists have formulated artificial flavors by synthesizing compounds with chemical structures similar to those of naturally occurring flavor molecules.

TECHNO FRONTIERS

1.2 CHEMISTRY IN INDUSTRIES AND TECHNOLOGY


ACTIVITY 1.2 New Construction Materials

Materialspen, questionnaire, reference materials

Procedure

1. Interview some residents in your community about the kinds of construction materials used in building their houses. As much as possible, include as your interviewees those who live in traditional Filipino houses, such as wooden houses and bahay na bato.

Prepare questionnaires beforehand. Include Table 1.2 in your questionnaires. Note the example given. Furthermore, ask your interviewees to explain their choices of building materials.

TABLE 1.2 MATERIALS USED IN BUILDING HOUSES

Traditional Houses Modern Houses

Roof Nipa Galvanized iron

Post

Wall

Floor

Window

Plumbing

Ceiling or wall insulator

Fig. 1.2 Different products of chemistry


2. For each material used in modern houses, research on the following:a. its characteristics compared to those of the corresponding materials used in

traditional housesb. the history of its discovery or invention and other uses

Questions1. In what ways do materials used in modern houses better satisfy the

requirements in house construction? 2. What role has chemistry played in the improvement of construction materials?

In this activity, you have learned that the invention of new materials, which satisfy more challenging conditions in the present environment, helps people live a modern lifestyle.

Continuing scientific research has resulted in new and improved methods of chemical analyses and industrial processes. These developments have, in turn, reduced production costs, improved the quality of goods, and in some cases even minimized waste and environmental pollution.

The following are examples of the beneficial application of chemical processes and analyses:

1. Sometime in the 1970s, foreign countries rejected peanut butter exported by the Philippines, charging that this contained aflatoxin, a toxic substance that develops from fungal contamination. Many of our manufacturers and exporters suffered big financial losses as a result. Since then, peanut butter manufacturers have been more conscious of the quality of peanuts that they use. Chemists, for their part, have developed fast detection tests and testing kits for aflatoxin.

2. Cooking and other forms of food processing involve chemical changes. An example is converting cassava, camote, or ube tubers into the more delectable cassava cakes, camote or ube pies or chips, and ube candies. The application of heat altered and improved the texture and appearance of the tubers. Other food products have been fortified with vitamins and minerals to make them more nutritious.

3. Aloe vera extract is a popular ingredient in medicines, shampoos, soaps, hair conditioners, and body lotions. Other herbs and natural scents have been incorporated in air fresheners, deodorants, washing liquids, fabric softeners, tissue paper, and detergents.

4. Special paper for photocopiers and fax machines, color films that can be processed and printed within an hour, and newspapers with colored pictures are all products of technology. Detergents, insecticides, bathroom tissue, ball pens, fruit concentrates, cosmetics, instant noodles, and wash-and-wear apparel are also products of modern chemical technology.


5. Petroleum from the Middle East and other Asian countries is distilled and processed to produce kerosene, gasoline, diesel oil, bunker fuel, asphalt, and the like. Gasoline can bring both good and harm. Although it serves us well as fuel for vehicles, when it is used in old engines, inefficient or incomplete combustion can release exhaust gases such as carbon monoxide, nitric oxide, and sulfur oxide. These gases are highly hazardous to health and property and they cause air pollution. There are different researches being conducted to improve the processing of gasoline so that the amount of harmful exhaust gases released is reduced.

Another problem arising from the use of petroleum is the accumulation of lead in the environment. Lead is used as an additive in gasoline to ensure better engine performance. This element has been found to cause physical abnormalities in unborn children. It can also harm adults who have been exposed to it for a long time. Chemists in petroleum firms have discovered substitutes for lead. Unleaded gasoline is now used as an environment-friendly alternative. However, recent chemical research has shown that these substitutes also have possible toxic effects on people. Thus, chemical research on environment-friendly fuel additives continues.

6. New chemical processes have paved the way for the development of more environment-friendly products, such as the improved types of refrigerants. Refrigerants are compounds used in a heat cycle which go through a change in phase from gas to liquid, and vice versa. In the past, the refrigerants we used contained chemicals such as chlorofluorocarbons or CFCs. CFCs are composed of the elements carbon, fluorine, chlorine, and hydrogen. When CFCs reach the ozone layer of the atmosphere, ultraviolet radiation from the sun’s rays breaks down the CFCs, freeing chlorine, which contributes to the destruction of the ozone layer. The ozone layer protects us from the harmful effects of ultraviolet radiation. The depletion of the ozone layer has directly contributed to the increase in the incidence of skin cancer. Refrigerants that are free of these harmful substances have been developed since.

7. Chemists have also formulated compounds that make plastics decompose over a period of time. These new types of plastics are biodegradable, which means that microbes can decompose them into simpler compounds.

In Activity 1.3, you will learn how chemical principles are applied in the manufacturing industry and how they can affect an industry and a community.


ACTIVITY 1.3 Chemical Processes in Manufacturing

Materials pen, paper

Procedure1. Visit an industrial plant or a manufacturing factory in your community.

Interview a chemist or chemical engineer in the factory.2. Choose one product manufactured by the factory to focus on. Ask your

interviewee the following: a. the raw materials used to make the productb. the processes involved in the manufacturing of the product and the

chemical principles involved in each stepc. how quality control of the product is carried out d. the waste products produced by the manufacturing process and how these

waste products are disposed of3. Prepare a simple schematic diagram of the manufacturing process.4. Conduct research and additional interviews as needed to find out how the

manufacturing process affects the environment and the lives of the people in the community.

5. Report your findings to the class.

Questions1. What are the roles of the chemists in the factory you visited? 2. Why is quality control important? 3. Are the waste products of the manufacturing process properly disposed of?

Explain.4. Do you think the presence of manufacturing plants in your community offers

more advantages than disadvantages? Explain.

The activity has provided you with a glimpse of industrial products and processes that help improve human life. These products and processes significantly contribute to the upliftment of living standards, but they also create certain problems. It is important that these products and processes be used in the best way possible, so that humans and the environment can fully benefit from them.

Do you also want to engage in product manufacturing someday? What products would you like to make? What processes will have to be carried out to make these products? Tell how these processes will affect living things and the environment.


Chemistry and TechnologyChemists are involved in various endeavors. They work in laboratories in the academe,

in government research agencies, and in many industries. They may also hold jobs involving the marketing and purchasing of chemicals, chemical instruments, and related products. They know the composition of materials used in manufacturing various products. They use apparatus to obtain and analyze information about natural or synthetic materials. They analyze sources of pollution and formulate ways to prevent or minimize pollution. They know how to recycle, reuse, or treat wastes. They conduct various chemical research studies and projects to address different problems involving chemistry.

Technology is the application of scientific principles. Chemical technology, therefore, is the use of chemical principles to improve processes or produce new materials. Chemists conduct studies to continuously upgrade existing technologies. Technology, however, has accompanying risks. To ensure safety, all possible hazards must be identified and assessed. Necessary measures must be taken to counteract them. There must be continuous research to find out if the disadvantages outweigh the advantages offered by such technology.

Products of technology influence not only the fields of science, but also the different aspects of human life. These influences may be felt directly or indirectly.

Fertilizers are natural or synthetic chemical substances or mixtures that are used to replenish the soil with nitrogen, phosphorus, potassium, and other elements that plants have used up. The elements sulfur, magnesium, and calcium are also among the elements present in fertilizers, but they are of secondary importance. Although fertilizers are important to modern agriculture, overuse of fertilizers can also have harmful effects on plants and soil quality. The leaching of fertilizer elements into bodies of water can lead to water pollution.

New polymeric products with revolutionary uses continue to be discovered by chemists. The usefulness of these polymers has increased considerably with the addition of plasticizers, extenders, fillers, pigments, antioxidants, and other additives. The polymerization process has given rise to many products, including fiberglass insulation binders, electrical insulation casings, paint resins, and wet-strength paper polymers.

Various types of chemicals are now widely used as pesticides. Synthetic pesticides are chemicals manufactured mostly from petroleum. Among the most important of these substances are the organophosphorus compounds, which are made up of carbon and phosphorus. These have been proven to be highly effective against a wide range of insect pests. Organophosphorus compounds, in general, quickly decompose into nontoxic substances. Therefore, their residues in treated soil, plants, or livestock do not cause any harm. However, these pesticides are effective only for a relatively short period of time. More frequent applications of these chemicals may be necessary.

Chemicals called herbicides are used to kill weeds and other unwanted or harmful types of plants. Some of these act against all kinds of plants, while others are highly selective. A third type of herbicide differs not only in its selectivity and type of plants targeted, but also in its mode of action. This type is either absorbed through the leaves


of plants or acts through the soil. Other types of herbicides, such as sodium chlorate, kill existing vegetation and act through the soil to prevent any further growth over a longer period. Most of these chemicals are organic. Some are derived wholly or in part from petroleum sources and frequently use petroleum-based solvents.

The effect of harmful chemicals on the environment is a worldwide problem. Global atmospheric changes such as the El Niño phenomenon, ozone depletion, and the greenhouse effect have been traced to the release of harmful substances into the atmosphere. Chemists discuss, explain, and analyze these phenomena in local and world conferences.

Together with microbiologists, chemists also study the effects of the release of biotechnologically engineered microorganisms into the environment. On the other hand, the results of biotechnological research in various parts of the world have benefited various fields such as agriculture, food science, and medicine.

A medical-waste disposal system that was first introduced in the United States has been adopted in Metro Manila hospitals. It is called the stericycle medical-waste collection treatment and disposal system. It is worry-free and more sanitary than our traditional method of treating medical waste. It helps protect medical professionals from the possible spread of disease-causing microorganisms. The ETD or electrothermal deactivation is the method used to treat these wastes. It employs an oscillating field of deeply penetrating, low-frequency radio waves. It heats the wastes to around 90°C, destroying the causative agents of disease, but not the plastic container of the waste. It has no air emission, no liquid discharges, and no chemicals to treat, store, or discard. It reduces waste residue by 95% in volume. The final end-products are disposed of in a landfill.

Fig. 1.3 Different chemical instruments and equipment


Over the years, chemical instruments and equipment have improved tremendously. Some features include faster resolution of data, easier preparation of samples, and more accurate results. As a result of chemical research, industries have also progressed quite fast, producing numerous useful products for homes and offices, transportation and communication, etc. We now have monorails and bullet trains, compact disks (CDs), analog disks, musical instruments, and fast-recording handy photo cameras. These are only some of the numerous inventions and innovations that have resulted from chemical research.

Work on Activity 1.4 and point out the different research undertakings that have given us useful products.

1.3 CONTRIBUTIONS OF CHEMISTRY TO OTHER FIELDS OF SCIENCE

ACTIVITY 1.4 Research Studies in Chemistry

Materialsworksheets, ballpen

Procedure1. Identify a product developed from the following:

a. polymers b. organophosphorus compounds c. herbicides d. waste

2. Research on the history of invention and commercialization or mass use of the following products of chemical technology. a. fertilizersb. drugsc. preservativesd. dairy products

QuestionWould you recommend that a new technology be commercialized as soon as it is invented? Explain your answer.

Principles in chemistry are readily applied in many other fields of science. One example is the field of health sciences and medicine. Medicinal chemists and pharmacists work as part of an interdisciplinary team for discovery and formulation of new drugs. The primary ingredients of these new drugs may be natural compounds taken from


plants, animals, and even microorganisms such as fungi. Research chemists help isolate or synthesize, purify, and characterize these chemical compounds. Afterward, a team of doctors and nurses performs chemical, microbiological, and clinical tests on rats and other laboratory animals. In these tests, data on the efficacy and safety of the drugs are gathered. If the results are favorable, the new drugs are then tested on selected patients. Only after these new drugs have passed all tests will they be approved for use in regular patients.

Strong plastic containers for blood or dextrose and opaque plastic bottles for drugs have helped improve the packaging of pharmaceutical products in terms of safety and sanitation. Synthetic rubber foams for hospital beds, inflatable rubberized mattresses, disposable syringes, and gloves for doctors and nurses are some of the products developed in the field of medicine.

In the field of agriculture, fertilizers and pesticides have been developed using the principles of chemistry. These agricultural chemicals make plants grow faster, bear more fruits, and resist pests and help prevent plant diseases. The raw materials from plants, insects, or animals are synthesized with the same chemical structure. These raw materials are then improved, purified, or used as naturally extracted. Additional chemical reactions may be carried out to produce the final composition of the fertilizer, soil enhancer, or pesticide.

One of the biggest global problems today is the shortage of food in many parts of the world. Research in food technology and nutrition has revealed alternative sources of food, such as high-protein yeast cells (HPYC).

Some studies have also shown how agricultural practices can be improved so that farmers can increase crop yield, cultivate plants over a shorter period of time, and ensure that these are pest-resistant and highly adaptive to weather changes. The International Rice Research Institute (IRRI) in Los Baños, Laguna has conducted numerous experiments to produce high-quality and highly productive rice varieties.

Since the last few decades, chemists have been teaming up with biologists and geneticists to produce genetically modified organisms (GMOs) in the field of biotechnology. A genetically modified organism is an organism whose genetic material is altered using genetic engineering techniques, generally known as recombinant DNA technology. In recombinant DNA technology, DNA molecules from different sources are combined into one molecule to create a new set of genes. This DNA is transferred into an organism, resulting in modified traits of this organism. Chemists’ research studies have resulted in GMOs, which are more disease-resistant and pest-resistant, leading to better varieties of economically important organisms.


Structural materials for buildings, machines, industrial reactors and tanks, bridges, roads, dams, jets, missiles, satellites, telecommunication facilities, etc., are all prepared using the theories, principles, and laws of chemistry and applying them in combination with those of physics and engineering. Some of these materials can withstand high temperatures and pressures, even in outer space or during earthquakes and other natural calamities. New materials in telecommunications have resulted in much faster transmission of information.

Before a college student can graduate with a degree in engineering, agriculture, nutrition, home economics, medical technology, physics, criminology, nursing, among other courses, he or she must take up a certain number of units in chemistry.

Fig. 1.4 Examples of genetically modified organisms

ACTIVITY 1.5 Chemistry Everywhere

Materialspen, questionnaire

Procedure1. Interview one of the following:

a. agriculture engineer b. doctor c. pharmacist d. medical technologiste. civil engineer

2. Ask the interviewee the following: a. What is the nature of your job?b. What major products or services does your company offer?c. How does the knowledge of chemistry help in your job?


QuestionAfter doing your interview, would you be interested in taking a profession related to chemistry? Explain.

1.4 BRANCHES OF CHEMISTRY AND THEIR APPLICATIONS

Clearly, chemistry has a valuable impact on other fields of science. Chemical research studies that explore the applications of chemistry must therefore be encouraged and supported by the citizenry and the government.

Chemistry has helped achieve milestones in other physical sciences and biological sciences. Many advances in chemical technology have been applied to other sciences as well. Medicine, engineering, agriculture, and the food sciences are some of these fields.

Chemistry has five branches, namely, inorganic, organic, analytical, physical, and biochemistry. Inorganic chemistry studies all other elements except carbon. Organic chemistry is concerned with compounds of carbon, hydrogen, and their derivatives. Analytical chemistry emphasizes the development of precise methods of analyzing the chemical components of substances. Physical chemistry covers chemical reactions, the energy associated with them, the nature of various states and phases of matter, and the structures of molecules, atoms, and subatomic particles. Biochemistry, which is the chemistry of life, includes the study of living systems and life processes at the molecular level, the raw materials that living organisms feed on, the products of these organisms, and the mechanisms by which life processes are accomplished. These branches of chemistry contribute to the discovery of various applications to meet most of humankind’s practical needs.

The pasteurization of milk is an application of biochemical research. Pasteurization is the process of heating liquids to destroy bacteria, protozoa, molds, and yeasts. New preservation techniques have made it possible to store liquid milk in packages that need little or no refrigeration. Research has also enabled milk producers to add vitamins and minerals essential for growth that are not found in ordinary cow’s milk. Most of us have grown up drinking processed milk (whole or nonfat milk), which has a longer shelf life. Nutritionists, however, have emphasized that mother’s milk contains nutrients that still make it best for babies.

Biochemistry has also been instrumental in the formulation of drugs for treatment of many human ailments, including serious diseases such as tuberculosis, leprosy, and malaria. Some illnesses that used to be incurable are easily cured today. An example is the eradicated disease called the bubonic plague. It is a curable disease by modern standards because of the availability of medicines produced as a result of experiments and research studies. There have been rare cases of this type of outbreak in modern times.


Research in nuclear chemistry (a subbranch of physical chemistry) has led to methods through which we can probe the human body without surgery. Various imaging techniques employing color-sensitive chemicals enable medical technologists to do the said methods. Some of these techniques use safe amounts of radioactive substances, such as cobalt-60, to detect diseased cells. Technetium-99 is used to detect brain tumors; it is found to localize more in brain tumors than in normal brain cells. A brain scan indicates the presence, size, and location of cancerous cells. This kind of diagnostic test detects ailments even long before the symptoms arise.

Organic chemistry has resulted in products obtained from petrochemicals and their derivatives. Special synthetic derivatives of petroleum are used in the production of plastic containers. Petroleum-based products used for fuel are constantly being improved to reduce air pollution.

For cars, trains, trucks, and buses, there are new products made of organic compounds that provide safety and convenience. We now have polyurethane bumpers that are capable of absorbing much of the impact during collision. The brake linings of vehicles are made of phenol formaldehyde resins, a tough and chemically resistant solid. As such, brake linings can withstand more friction, resulting in longer use. High levels of octane, another organic compound, are also added to fuels to improve the performance of car engines.

The spacesuits of astronauts and the metals, adhesives, and textiles used inside spaceships are made of specially formulated materials. They have high melting points. This means that they can withstand extremely high temperatures and friction.

In inorganic chemistry, new kinds of steel, such as alloys, have been found useful as metal molds for chemical instruments and machine parts. Telecommunication wires are made of modern materials such as fiber optics. These materials can have a large amount of information within seconds.

Fig. 1.5 A patient undergoing radiotherapy to treat cancer


The Department of Science and Technology (DOST) administers several offices and agencies involved in scientific research. One of its activities is plant research involving the development of new food products, such as corn-mango, corn-soy, squash, and other combinations that are marketed as nutricrunchies. These snacks, which contain 450–499 kilocalories (kcal) of energy, are good for active and growing children. The DOST also develops certain processes to produce baby food blends (corn-soy-shrimp powder, banana-peanut mix, mongo-camote-sesame, germinated rice-cowpea blend, etc.), fish protein concentrate, noodles, and bouillon cubes from fish proteins.

One of the councils under the DOST is the Philippine Council for Advanced Science and Technology Research and Development (PCASTRD). It is tasked to develop national capability in advanced technology. The PCASTRD has dynamically focused its efforts on development projects in the areas of material science, biotechnology, electronics, instrumentation and controls, information technology, and photonics technology.

The Philippine Council for Industry and Energy Research and Development (PCIERD), another DOST council, is tasked to plan, monitor, and promote scientific and technological research projects for applications in industry, energy, utilities, and infrastructure. The PCIERD gives financial and technical assistance to selected science and technology activities. Some successful chemical researches that were conducted under PCIERD grants were

1. development of alginates (sodium salt used as thickeners) from Sargassum seaweeds (for food and textile use);

2. development of a casting technique for aluminum bronze;

3. fabrication of complementary equipment for gemstone cutting and polishing machines;

4. pilot plant production of lysine (an amino acid);

5. derivation of antibodies from a single individual or cell for rapid screening of aflatoxin in food products and animal feeds;

6. production of penicillin G from a high-yielding strain, Penicillium chrysogenum 30T; and

7. Association of Southeast Asian Nations (ASEAN)–New Zealand Energy Program on natural gas utilization (NGU) for the transport sector.

1.5 CHEMICAL RESEARCH STUDIES IN THE PHILIPPINES


Our inventors, scientists, members of the academe, and industry experts have all contributed to the development of other products through their research undertakings. Annual conventions and science fairs in various parts of the country introduce us to the results of these research projects.

In 1976, Filipino scientists were officially organized into the National Academy of Science and Technology (NAST). The best and brightest scientists in the country became members of this premier Philippine scientific society.

One of the first 10 academicians of NAST who were selected from among 107 distinguished Filipino scientists and technologists was Alfredo C. Santos, PhD. He was chosen for his contributions to the chemistry of natural products and pharmacology of Philippine medicinal plants. He was also named 1978 National Scientist in the field of physical chemistry. His original experiments on numerous alkaloids that he isolated from Philippine medicinal plants earned him the President Magsaysay Distinguished Service Star in 1954.

In 1979, another famous Filipino organic chemist, Bienvenido O. Juliano, PhD, joined the NAST. He was named one of the country’s Ten Outstanding Young Men (TOYM) in the field of science in 1964. He finished his doctoral degree in organic chemistry at the Ohio State University in Columbus, Ohio, USA. By the age of 42, more than a hundred scientific articles that he authored had been published in local and international journals. His research studies dealt with starch and proteins in relation to the grain quality of rice.

In 1980, the NAST admitted seven new members. One of them was a well-known biochemist and author of organic and biochemistry books used in Philippine universities. Clara Y. Lim-Sylianco, PhD, a University of the Philippines professor, did significant research on mutagens, antimutagens, and anticarcinogenic chemicals found in different fruits and vegetables. She held the UP Endowment Professorial Chair in Chemistry from 1974 to 1977. She obtained her doctorate degree in biochemistry and organic chemistry from the University of Iowa.

1.6 OUTSTANDING FILIPINO AND FOREIGN CHEMISTS

Fig. 1.6

Fig. 1.7

Fig. 1.8


Foreign luminaries in chemistry include the following:

1. Antoine-Laurent Lavoisier of France − He was known as the father of modern chemistry.

2. John Dalton of England − He was an advocate of the atomic theory.

3. Svante August Arrhenius − He was the founder of physical chemistry.

4. Giuliana Tesoro − She is an Italian-American expert in the science and technology of polymers.

5. Marie Curie − She was a French chemist who discovered radioactivity.

Fig. 1.9

Fig. 1.10

Fig. 1.11

Fig. 1.13

Fig. 1.12


6. Joseph John Thomson − He discovered electrons.

7. Eugene Goldstein − He discovered protons.

8. James Chadwick − He discovered neutrons.

9. Wilhelm Röentgen − He discovered the radiations emitted by materials.

10. Henri Becquerel − He observed the penetrating radiation given off by uranium.

11. Ernest Rutherford − He explained the theory on radioactivity.

Fig. 1.14

Fig. 1.15

Fig. 1.16

Fig. 1.17

Fig. 1.18


Chemistry is involved in a wide array of disciplines. There are many fields or professions related to chemistry that you can pursue in the future. The following is a list of specialists or experts in chemistry and other related careers.

Biochemists

They employ the techniques and theories of chemistry to understand and study the molecular basis of life. Biochemists study the chemical effects of food, drugs, and hormones on the body processes of living organisms.

Analytical Chemists

They identify the kind and quantity of a substance present in a material. Analytical chemists are involved in quality control with respect to food, pharmaceutical, and industrial products.

Forensic Chemists

Their job usually includes examination of blood, hair, skin, cloth, paper, paint, or other materials that can be used to help solve a crime. They usually work in a police agency or investigation bureau. Accuracy and precision are essential to their line of work.

Inorganic and Organic Chemists

Inorganic chemists conduct research studies on substances without carbon. Their major concerns are materials such as those found in mineral ore. On the other hand, organic chemists undertake research on substances whose primary component is carbon.

Physical Chemists

They deal with the physical properties of substances and the relationships involving energy and matter.

Chemical Engineers

Chemical engineers are involved in the development of processes and in the design and operation of plants where materials undergo physical or chemical changes.

Pharmacists

The collection, preparation, and standardization of drugs and medicines are major parts of their work. They are responsible for preparing and dispensing medications prescribed by physicians, dentists, and veterinarians.

1.7 CAREERS IN CHEMISTRY


The diagram below enumerates numerous professions that apply principles in chemistry.

Field/Subject Occupation

—Pure Sciences

Fig. 1.19 Some chemistry-related careers

Chemistry

—Physicist—Biologist—Geologist—Meteorologist

—Agriculture

—Engineering

—Technical

—Agronomist—Forester—Horticulturist

—Chemical Engineer—Ceramic Engineer—Environmental Engineer—Metallurgical Engineer—Nuclear Engineer—Sanitary Engineer—Mining Engineer—Industrial Engineer

—Draftsman—Machinist—Photoengraver—Photographer—Spectroscopist —Dentist

—Dietitian—Medical Technologist—Food Technologist—Physical Therapist—Pharmacist—Veterinarian—Toxicologist—Anaesthesiologist

Health Sciences

—Applied Sciences


I. Enriching Your Science Vocabulary

Fill in each blank with the correct word. Choose from the words inside the box.

breakthrough process

chemistry technology

innovation

1. The organized knowledge that deals with changes in the structure, composition, and properties of matter is known as _______________________.

2. When a great discovery is made, such as the invention of a new wonder drug, we call it a _______________________.

3. The use of fiber optics in telecommunication wires is an example of _______________________.

4. The series of steps or methods of making an object is called _______________________.

II. Assessing Your Knowledge

Answer the following briefly.

1. Choose one chemical product or process. How does it affect your daily life and our society as a whole?

2. How important is the involvement of chemistry in other fields of science? Explain.

3. Cite and describe an example of chemistry’s involvement in each of the following fields:

a. medicine b. agriculture c. engineering d. architecture

Chapter Review


The study of chemistry entails several experiments. These experiments will allow you to observe firsthand different chemical principles. These experiments require the use of scientific equipment and apparatus, which you need to be familiarized with for you to perform experiments successfully. What are some of these laboratory equipment? Find out in this chapter.

In this lesson, you will be introduced to glassware used in performing experiments in chemistry. You will learn how to use them safely and properly in your laboratory preparations and analyses, so that you may obtain precise and accurate results. The use of these types of glassware is crucial to the successful performance of experiments.

You can use the following kinds of glassware as containers: test tube, beaker, Erlenmeyer flask, Florence flask, evaporating dish, and watch glass. Burettes, graduated cylinders, and pipettes are used for measuring the volume of liquids. They come in various sizes. Changes in color, texture, and physical state can be observed very clearly when transparent glass containers are used.

Laboratory glassware is made of borosilicate glass, which can withstand high temperatures. This material also withstands chemical attack more efficiently than most materials for glass manufacture. Because of these properties, it is widely used for laboratory work, as well as serving dishes. Moreover, borosilicate glass can be shaped and blown by amateur glass blowers. It has an advantage over materials, such as plastics, because of its extreme resistance to chemicals and its ability to undergo abrupt temperature changes without breaking. It is used by science researchers in experiments involving heat, which can cause ordinary glass and plastic to break or melt.

Chapter 2COMMON LABORATORY APPARATUS, EQUIPMENT,

AND TECHNIQUES

2.1 GLASSWARE USED IN CHEMISTRY LABORATORY

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Technology

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