Bell-ringer Think critically. We say that everything has mass. Name some ways we can prove that air has mass. Which is heavier, a pound of feathers, or.

Bell-ringer

Think critically. We say that everything has mass. Name some ways we can prove that air has mass.

Which is heavier, a pound of feathers, or a pound of lead?

Answer the questions on the Section 1-1 Review on page 5. Answer all four questions, but you do NOT have to write the questions.

Our lab safety quiz will be on Friday!

Section 1-2Matter and Its Properties

Coach KelsoeChemistryPages 6–14

Matter and Its Properties

Matter is defined as anything that has mass and takes up space.

Mass is a measure of the amount of matter in an object.

Volume is the amount of three-dimensional space an object takes up.

Matter comes in many different forms.

Basic Building Blocks of Matter

The basic building blocks of matter are atoms and molecules.

An atom is the smallest unit of an element that maintains the properties of that element.

An element is a pure substance made up of only one kind of atom.

A compound is a substance that is made from the atoms of two or more elements that are chemically bonded.

Basic Building Blocks of Matter

A molecule is the smallest unit of an element that retains all the properties of that element or compound.

Think of it like Play-Doh.

Atom, Element, Compound, or ATA

Hydrogen? Carbon dioxide? Pure gold? Water? Carbon? Glucose (C6H12O6)? Calcium?

Bell-ringer

Identify whether the following substances are elements or compounds.ButaneRadonChlorofluorocarbonNitric acidZincLimePhosphorus

Properties and Changes in Matter

Every substance has characteristic properties. Properties can help reveal the identity of an

unknown substance. There are two types of properties:

Extensive- depend on the amount of matter that is present; volume, mass and amount of energy

Intensive- do not depend on the amount of matter present; melting point, boiling point, density, and conductivity of electricity and heat.

Physical Properties and Physical Changes A physical property is a characteristic that

can be observed without changing the identity of a substance; examples include density, color, taste, hardness, melting and boiling points

A change in a substance that does not involve a change in the identity of it is a physical change. Examples include grinding, cutting, melting, and boiling a material.

Changes of State

Melting and boiling are part of an important class of physical changes called changes of state.

A change of state is a physical change of a substance from one state to another.

The three common states of matter are solids, liquids, and gases.

There is a fourth state that is less common, called plasma.

States of Matter

Matter in the solid state has definite volume and definite shape; example: rocks, glass

Matter in the liquid state has a definite volume, but no definite shape; example: water

Matter in the gas state has no definite volume or definite shape; example: helium, oxygen

Plasma is a high temperature physical state of matter in which atoms lose their electrons; example: fluorescent light bulb

Bell-Ringer

Identify the following as an element or compound:Sulfur dioxideRadiumCarbon sulfateEinsteiniumAntimonyPhosphoric acid

Changes of State

Solid

Liquid

Gas

FreezingMelting

CondensationEvaporation

Bell-ringer

What is a physical property? Give an example.

What is a physical change? Give an example.

What do we call the changes from solids to liquids, liquids to gases, and vice versa?

Chemical Properties and Chemical Changes

A chemical property relates to a substance’s ability to undergo changes that transform it into different substances. An example would be the ability of charcoal to burn in air to form carbon dioxide, and iron rusting to form iron oxide.

A chemical change is a change in which one or more substances are converted into different substances.

Chemical Properties and Chemical Changes

A chemical change is also known as a chemical reaction.

The substances that react in a chemical change are called the reactants.

The substances that are formed by the chemical change are called the products.

In burning charcoal (carbon), the carbon mixes with oxygen to form carbon dioxide.

Burning Charcoal

Technically, we say that “carbon plus oxygen yields (or forms) carbon dioxide.”

But…

We can write it like this:

Carbon + oxygen carbon dioxide

Energy and Changes of Matter

Any time physical or chemical changes occur, energy is always involved. It can take many different forms, like heat or light.

Even though energy can be absorbed or released in a change, it is not created or destroyed. It just turns into a different form.

The amount of energy on Earth does not change!

Classification of Matter

All matter can be classified into one of two groups:Pure substancesMixtures

A pure substance has a composition that is the same (or uniform) throughout.

A mixture contains more than one substance.

Mixtures

A mixture can usually be separated by different means.

A homogeneous mixture has a uniform composition. “Homo” means “same.”

Sometimes homogeneous mixtures are called solutions.

A heterogeneous mixture is not uniform throughout. “Hetero” means “different.”

Bell-ringer

What is chemistry? How many main branches of chemistry are

there? What type of research is considered to be

done for knowledge only, usually due to curiosity?

Don’t forget the lab quiz tomorrow!!!

Separating Mixtures

There are several ways to separate mixtures: Filtration Distillation Crystallization Magnetization Chromatography Others

Pure substances

A pure substance is different from a mixture in two ways:Every sample of a given pure substance has

exactly the same characteristic properties.Every sample of a given pure substance has

exactly the same composition. Pure substances are either compounds or

elements.

MatterCan it be separated?

Mixtures

Is the compositionuniform?

Pure Substances

Can it be decomposed by ordinary chemical

means?

HomogeneousMixtures

(air, sugar in water,stainless steel)

Compounds(water, sodium,

chloride, sucrose)

HeterogeneousMixtures

(granite, wood,blood)

Elements(gold, aluminum,oxygen, chlorine)

Yes No

Yes No Yes No

Bell-ringer

What are the two ways we can classify matter?

Which one can we separate into separate components?

List four ways we can separate them.