Matter

Pure Substances

Elements

Compounds & Molecules

Mixtures

Homogeneous

Solution

Heterogeneous

Matter

Matter is anything that has MASS and takes up SPACE

Law of Conservation of Mass: Matter cannot be created or destroyed

Matter

Examples of Matter:• Water• Chex Mix• Plastic• Humans• Air

Examples that aren’t Matter:• Space• Light• Sound• Energy• Heat

The Atom: The unbreakable building blocks that make up all matter

Nucleus:Middle of the atom, made up of protons (+ charge) and neutrons (no charge)

Electrons ( - charge)

Physical Properties

All matter has physical and chemical properties

Physical Properties are properties that you can measure or see

Examples: mass, density, color, temperature, malleability and brittleness, phase (solid, liquid, gas)

Physical Changes

Physical changes change the physical properties but DO NOT change the matter into something else• Phase Changes• Changing Shape

Physical Changes are reversible

Chemical Properties

Chemical Properties are properties that allow the ability for a chemical change/reaction to occur

They can only be observed when matter goes through a chemical change, can’t know just by looking at itExamples: Flammability, Ability to react with specific materials

Chemical Changes

Chemical Changes: Any change that changes one substance into a different substance

Created by a chemical reaction

Chemical changes are very difficult or impossible to undo

Signs of a Chemical Change

Types of MatterMatter is separated into two major categories:

1) Pure substance cannot be separated into different kinds of matter by physical means and are made up of one single chemical throughout

2) Mixtures are made up of multiple substances

Most matter in the world around us are mixtures

Matter

Pure Substances

Elements

Compounds & Molecules

Mixtures

Homogeneous

Solution

Heterogeneous

Elements

Element: a substance that cannot be separated into simpler substances by chemical means• Each element is a unique type of atom• Atoms of the same element are all similar to

each other and different from atoms of any other element

• Elements are located on the periodic table

Periodic Table Layout

Organized into periods (rows) and groups (columns), elements separate from the table are part of Periods 6 and 7

Periodic Table

Element Symbol: 1 or 2 letters that represent the elementFirst letter is ALWAYS capitalized, second letter NEVER is

Atomic Number: Number of Protons

Atomic Mass

The atomic mass listed for an element on the periodic table is the mass of a single atom in atomic mass units (amu)

1 amu = 1.66 x 10-24 grams

Atomic mass units are not practical for experiments, our balances can’t measure a mass that small

Atomic MassTo turn amu into something more usable in lab we use a unit called the mole

1 mole = 6.02 x 1023 atomsThis is Avogadro’s Number

Atomic Mass = Number of grams in 1 mol

Calculating Moles using Atomic Mass

Use atomic mass as a conversion factor between moles and grams

How many moles are in a 10.0g sample of Carbon?

10.0 grams x 1 mole = 0.833 moles 12.01g

Try it on your own

You have 20 grams of Helium, how many moles do you have?

Calculating Mass from Moles

You have 5 moles of Nitrogen, how many grams do you have?

5 moles x 14.00 grams = 70 grams1 mole

Try it on your own

You have 2 moles of Lithium, how many grams do you have?

Matter

Pure Substances

Elements

Compounds & Molecules

Mixtures

Homogeneous

Solution

Heterogeneous

Review - Types of MatterMatter is separated into two major categories:

1) Pure substance cannot be separated into different kinds of matter by physical means and are made up of one single chemical throughout

2) Mixtures are made up of multiple substances

Most matter in the world around us are mixtures

Compounds and Molecules

Compounds and molecules are pure substances

They cannot be separated by physical means but can be separated by chemical means

Their physical and chemical properties come from the shape of the molecule, not from what they are made of

Compounds vs. Molecules

A molecule is ANY group of atoms chemically bonded together

Examples: H2 (Hydrogen Gas) CH4 (Methane)

N2 (Nitrogen Gas)

Compounds vs. Molecules

A compound is a substance containing DIFFERENT elements that are chemically bonded together.

Examples: H2O (Water)

C2H6O (Ethanol)

NaCl (Salt)Almost everything in this world is made of compounds!

Understanding Chemical Formulas

Chemical formulas are written using element symbols

Remember: Element symbols can have either 1 or 2 letters and ALWAYS start with a capital letter!

Chemical Formula PracticeHow many different elements are in each molecule?

NaCl KI

HCN KCl

MgO Xe

Subscripts

Subscripts are used to tell you how many copies of an element is in a molecule

H2 = 2 Hydrogen in one element

H2O = 2 Hydrogen, 1 Oxygen in one element

Practicing Reading Subscripts

H(CO3)2

How many H’s

How many C’s

How many O’s

H2SO4

How many H’s?

How many S’s?

How many O’s?

Molar Mass

Molar mass = Number of grams in one mole of the molecule

You need to add up the atomic mass of each element (multiplied by any subscripts) to get the total mass of the molecule

Practicing Molar Mass

Molar Mass of HCN

Mass of Hydrogen: 1.008Mass of Carbon: 12.01Mass of Nitrogen: 14.01

Molar Mass of HCN = 1.008 + 12.01 + 14.01 = 27.03 g/mol

Molar Mass of H2SO4

Mass of H: 1.008 x 2Mass of S: 32.07Mass of O: 16.00 x 4

Molar Mass of H2SO4 =

2.016 + 32.07 + 64.00 = 98.09 g/mol

Converting between grams and moles for molecules

Converting between grams, moles, and atoms is the same process for molecules as it is for individual elements

Instead of using atomic mass to convert between grams and moles you need to use the molar mass of the molecule

Molecule Conversion Example

You have 100 grams of Table Salt (NaCl), how many moles do you have?

100g NaCl x 1 mol NaCl = 1.71mol NaCl

58.44g NaCl

Molar Mass

Molar mass = Number of grams in one mole of the molecule

You need to add up the atomic mass of each element (multiplied by any subscripts) to get the total mass of the molecule

Percent (%) Composition

Remember from Lab 1C

% composition = mass of the part x 100

mass of the whole

We can find the Percent Composition of a molecule the same way

Percent Composition of Molecules

% comp = molar mass of element x 100

molar mass of molecule

Example: What percentage of the mass of H2SO4 comes from the Oxygen?

Mass of O: 16.00 x 4 = 64 g/molMass of H2SO4: 98.09 g/mol

% Oxygen: (64/98.09) x 100 = 65.2%

Percent Composition Example

Find the Percent Composition of both Copper and Chlorine in CuCl2

Molar Mass of Copper:Molar Mass of Chlorine:Molar Mass of Molecule:

% composition of Copper:

% composition of Chlorine:

Matter

Pure Substances

Elements

Compounds & Molecules

Mixtures

Homogeneous

Solution

Heterogeneous

Mixtures

Mixtures: Matter that contains more than one substance

Mixtures can be separated by physical means- sorting, filtering, heating, or cooling

Types of Mixtures

Homogeneous Mixtures looks the same throughoutHeterogeneous Mixtures look different throughout

Examples of MixturesDecide whether each mixture is a homogeneous mixture (HoM) or a heterogeneous mixture (HeM)

SoapChocolate Chip CookieGraniteGatoradeShampoo

Chex MixSandLemonadeGranola BarMilk

Matter

Pure Substances

Elements

Compounds & Molecules

Mixtures

Homogeneous

Solution

Heterogeneous

Solutions

Solutions are a specific type of homogeneous mixture where one substance (solute) gets dissolved in another substance (solvent)

The substance being dissolved (the solute) completely breaks down and gets absorbed by the solvent:

Examples: Salt Water, Pop, lemonade