CP Chemistry – January 23, 2007

• 1) Welcome! Please choose any seat with a green sheet.

• 2) Complete the student information sheet on your desk.

CP Chemistry – January 23, 2007

• 1) Complete Student Information Sheet

• 2) Review Course Syllabus

• 3) Notes: Introduction to chemistry

• 4) Activity: Expectations for course

• 5) Complete Textbook Questionnaire

• 6) Homework: Syllabus Quiz & Interviews

CP ChemistrySpring 2007

Chemistry January 25, 2007

• 1) Notes on Chemistry & Branches

• 2)

Introduction to Chemistry• Chemistry is the study of the

composition of matter and the changes they undergo

Opportunities for Chemists• Chemists are involved in a variety of different

jobs that include the following:

• a. Textiles

• b. Cosmetics

• c. Development of new medicines such as AZT

• d. Research

• e. Analysis of Substances’ Compositions

Branches of Chemistry• Chemistry has 5 main branches:

• a. Organic Chemistry: study of substances that contain carbon

• b. Inorganic Chemistry: study of substances that do NOT contain carbon

Branches of Chemistry Cont• c. Physical Chemistry: deals with the

applications of theories and experiments to describe the behavior of substances

• d. Analytical Chemistry: deals with the composition of substances

• e. Biochemistry: study of the chemistry of living things

Practicality of Chemistry• Chemistry is practical in that it can be

applied to improving the lives of humans

• Technology is the application of scientific knowledge to improve the quality of life for humans

Homework Assignment• You are to interview three (3) individuals who had

taken high school Chemistry previously. Record their responses to the following questions:

• 1. Describe your high school Chemistry experience. (What did you learn? How do you remember it?)

• 2. Describe the relevance of Chemistry to your daily life. In other words, describe situations where Chemistry improves your life

Review Questions• Determine which field of chemistry would most likely

do the following:• a. Predict how a liquid will react as it is cooled to

absolute zero• b. Study the nutritional value of vitamin E in the body• c. Determine the percentage of Calcium ions in ocean

water• d. Study the compounds of nitrogen

Early History of Chemistry• Science is a continuously changing process

• Early pioneers in chemistry were called alchemists

• Alchemists first appeared with the Taoists in China and Pythagoreans in Greece after the 6th century BCE

Alchemists• Alchemists sought to transmute (or change) one

substance into another– usually they tried to turn lead into gold

• Early alchemists developed many techniques still used today such as distillation as well as specially shaped bottles such as flasks

History of Chemistry Continued• Chemistry is derived from an Arabic word

meaning “gold cooking”

• Alchemy declined in the late 1400s as the field of medicine began to grow

Growth of Chemistry From Alchemy• In 1606, King Charles II formed the “Royal

Society of London.”

• This group used the scientific method to study matter in addition to what alchemists had learned

Matter and Properties

• Matter is anything that has mass and takes up space

• Matter makes up everything

Matter and Properties

• There are four states of matter:

• Solid

• Liquid

• Gas

• Plasma

Solids• Solids have definite shape and volume

• The particles are tightly packed together

• Examples of Solids:

• Coal, Sugar, Gold

Liquids• Liquids have a fixed volume but change shape

• The particles are NOT as tightly packed together as a solid

• Examples:

• Water, Milk

Gases• Gases do NOT have a definite shape or

volume

• The particles are very loosely packed together

• Examples:

• Oxygen, Carbon Dioxide

• Liquids and Gases both take the shape of their containers

Plasma• Plasma is the most common state of matter

in the universe

• It is not commonly found on Earth

• Plasma is a gaseous mixture of electrons and positive ions

Plasma• Examples:

• Fluorescent and Neon Lights

• The Sun

• Plasma is produced by heating a gas to an extremely high temperature

Classwork Activity• Arrange the four states of matter in order of

• a. The closeness of the molecules to each other

• b. Provide examples of each type of matter

Wiki – Phases of Matter

• Address: www.chemiwiki.net/php

Physical Properties• Physical Properties are properties that can

be measured without changing the substance’s composition

• Examples:

• Color, Mass, Melting Point

Physical Change• Physical Changes are any changes to a

substance that still causes the substance to retain its original properties that it had before

• Examples:

• Melting, Boiling, Cutting, Sublimation

Activity• Determine which of the following represents

a physical change:

• a. The freezing of water to form ice cubes

• b. The generation of carbon dioxide from Alka Seltzer tablets

• c. The cutting of wood

Chemical Properties• Chemical Properties are the ability of

different substances to undergo chemical reactions and form new substances

• Examples:

• The burning of wood

• Milk turning sour

• Leaves changing color in the fall

Chemical Changes• A chemical change occurs when a substance

undergoes a change in composition

• New substances are always formed during a chemical change

• Example: the combustion of methane (CH4) to form H2O and CO2

Chemical Changes Continued• Chemical Changes usually require or

release energy

• Evidences of a chemical reaction:

• a. Evolution of Light and Heat

• b. Production of a gas

• c. Formation of a solid

Classifying Substances• Substances can be classified into the

following three groups:

• a. Mixtures

• b. Elements

• c. Compounds

MatterCan the substance be separated by ordinary physical means?

YES

NO

Mixture

Element or Compound

Elements• Elements are composed solely of one type

of substance

• Examples:– Fe, Iron; O2, Oxygen; Ca, Calcium

• Elements cannot be broken down further

Compounds• Compounds are composed of two or

more elements

• Compounds can only be chemical broken down into component elements

• Examples:

• CO2 and H2O

Mixtures• Mixtures are a combination of two or more

different types of matter

• The different types of matter are not chemical mixed together

Mixtures

• Mixtures can be separated through physical means

• There are two types of mixtures:

• a. Homogeneous Mixtures

• b. Heterogeneous Mixtures

Homogeneous Mixtures• Homogeneous Mixtures appear to

be composed of only one form

• They are uniform in composition

• Examples:

• Coffee & Salt Water

• A solution is another name for a homogeneous mixture

Heterogeneous Mixtures• Heterogeneous Mixtures are composed of

two or more different forms

• They are NOT uniform in composition

• Examples: Sand and Spaghetti Sauce with Meatballs

E lement sO n e Typ e o f A tom

CompoundsTw o or M ore D iffe ren t

Typ es o f A tom s

S ubst ance(C an W rite C h em ica l F orm u las ;

C on ta in O n ly O n e Typ e o f M atte r)

H omogeneousU n ifo rm C om p os it ion

H et er ogeneousN on -u n ifo rmC om p os it ion

M ix t ur es(C om p osed o f Tw o D iffe ren t

Typ es o f M atte r)

M at t er

Homework• Find 5 substances at home and classify

them as to element, compound, heterogeneous, and homogeneous mixture. You must find one substance the represents each category of classification

Practice• Classify each of the

following as element, compound, heterogeneous mixture or homogeneous mixture

• a. Chlorine• b. Water• c. Soil• d. Sugar Water• e. Oxygen• f. Carbon Dioxide• g. Rocky Road Ice Cream• h. Alcohol• i. Pure Air• j. iron

Chemical Symbols• A chemical symbol is a short hand

abbreviation for each element

• Examples:

• HydrogenH

• Iron Fe

• The symbols come from the English or Latin name for the element

Chemical Reactions• In a chemical reaction, one or more

substances change into a new substance

• Reactants are the original substances present in a chemical reaction

• Products are the new substances produced

Chemical Reactions Continued• Chemical reactions are always written in the

following manner:

Reactants Products

Practice: Identify the reactants and products in the following:

• 1. H2 + O2 H2O

• 2. Mg + O2 MgO

• 3. HgCl2 Hg + Cl2

• 4. Fe(OH)3 + HCl H2O + FeCl3

Law of Conservation of Mass• Law of Conservation of Mass states that

mass is neither created or destroyed in a chemical reaction

• If 5 g of Na reacts with 10 g of Oxygen completely, what mass of NaO is produced?

Law of Conservation of Mass Cont• 1) 45 g of hydrogen reacts with 60 g of

oxygen. How much H2O is formed?

• 2) If 500 g of KClO3 decomposes and produces 303 g of KCl, how many grams of O2 are produced?

• 2 KClO3 2 KCl + 3 O2

Law of Conservation of Mass Continued

• 3. How much CO2 is produced from 200 g of CaCO3 decomposing if 112 g of CaO are produced?

• CaCO3 CaO + CO2