Matter and Change

Chapter 1

Anything that bites or scratches is biology.

Anything that snaps or bubbles is

chemistry.

Anything that doesn’t work is physics.

Chemistry is the study of composition,

structure and properties of matter and the

changes it undergoes.

Branches of Chemistry

Organic Chemistry- carbon containing

compounds

Inorganic Chemistry- noncarbon

containing compds.

Physical Chemistry- matter’s relationship to energy

Analytical Chemistry- Identification of matter

Theoretical Chemistry- the use of mathematics and computers to understand chemical behavior and design and predict new compds.

Definite Composition

A chemical is a substance with definite

composition.

Definite composition means it has the

same proportion of atoms that make it

up.

Ex. H2O Water always has 2 atoms of

hydrogen and 1 oxygen atom

Research

Basic Research-for increasing knowledge

Ex. What are electrons made of? What is

Saturn’s atmosphere made up of?

Applied Research-for solving a problem

Ex. A cure for AIDS, Developing a substitute

of Freon that does not harm the ozone in the

upper atmosphere

Technology

Technological Development

Producing products that improve our quality

of life

Ex. Catalytic converters that reduce air

pollution from cars.

Section review p. 7

Matter

Matter- anything that has mass and

volume

Mass- amount of matter

Weight- depends on gravitational pull

Volume- amount of space

Building Blocks of Matter

Atom- smallest unit of an element that keeps the properties of that element.

Element- Pure substance that made up of only one kind of atoms.

Compound- substance made up of two or more elements chemically bonded.

Properties

Chemists use properties to distinguish

between substances and to separate

them. By comparing several properties

of a subst, an unknown subst can be

identified.

Properties

Extensive property- depend on the

amount matter such as mass

Intensive property- does not depend on

the amount of matter, such as odor.

Types of Properties

• Extensive properties depend on the amount of matter.

Examples: size, mass, weight, volume

• Intensive properties depend on the type of matter.

Examples: absorbency, flammability, ability to rust, hardness,

melting point, density

Extensive or Intensive?

Property Extensive Intensive

Waterproof

Mass = 600 g

Good insulator

Elastic

Circumference = 75 cm

✔

✔

✔

✔

✔

Physical Properties

Physical Properties- can be observed or measured without changing the identity of the subst

Ex. Observing and measuring the boiling pt of water

Physical Change- a change that doesn’t involve changing the identity of the subst

Ex. Liquid water changing to water vapor when boiled

Physical States of Matter

Solid- definite shape and volume.

Particles tightly packed in fixed positions

and can only vibrate.

Liquid- definite volume, indefinite shape.

Particles can flow past each other (fluid)

Gas- indefinite shape, indefinite volume,

fluid. Particles move more rapidly with

lots of space in between. Particles take

up volume and shape of container

Plasma- high temperature matter where

atoms lose their electrons. Ex. The sun

Chemical Properties

Chemical Properties- substance's ability

to undergo changes to form new

substances

Ex: ability of iron to react with oxygen to

form rust

Chemical Change

Chemical Change or Chemical Reaction-

change where one subst is changed to a

new subst

Energy is always involved in chemical

and physical changes

Chemical Reaction/change

Chemical Reaction: Reactant Product

Ex. Carbon plus oxygen yields (forms or produces)

carbon dioxide

Rxn:

Note:

products of a chemical change or reaction have properties very different from the reactants. Consider what carbon and oxygen gas is like and what carbon dioxide is like.

Chemical Changes

Compounds can be broken down into simpler substances through

chemical changes, but elements cannot.

Carbon + water vapor

Sucrose

Chemical Changes, cont.

A chemical change produces matter with a different

composition from the original matter.

Chemical Changes, cont.

A chemical change produces matter with a different

composition from the original matter.

Sodium chloride

Classification of Matter

Mixture- blend of two or more kinds of matter,

each with its own identity and properties

2 types of mixtures:

Homogeneous mixture or solution- uniform

throughout Ex. Kool aid drink, 14k gold

Heterogeneous drink- not uniform throughout

Ex. Sample of dirt

Pure Substance

Pure substance- a substance with the

same properties throughout and same

composition throughout

Ex. Pure water has same lack of taste, color,

boiling pt, density… It is always made up of

11.2% hydrogen and 88.8% oxygen by mass

1. Silver sulfide is a(n) .

Pure Substances

2. An example of an element is . carbon, sodium, silver, etc.

compound

An element is the simplest form of matter that has a unique

set of properties.

A compound contains two or more elements that are

chemically combined in a set ratio.

3. is an example of a compound. C6H12O11, CO2, NH4, etc.

Substances Mixtures

Can be separated

physically

Can be separated

chemically

How Is Matter Classified?

Classifying Matter

Stainless steel Mercury sulfide Granite Mercury

Since water is a compound it can be

broken down into its elements.

Electrolysis is used to break down water

to hydrogen and oxygen

Section Review p. 18

Flow Chart

Matter

Pure Substances

Elements Compounds

Mixtures

Homogeneous Mixtures

Heterogeneous mixtures

Would you want to eat this for breakfast?

Chemistry and You

Practice: Element or Compound?

When a certain blue-green solid is heated, a colorless gas

and a black solid form. All three materials are substances.

Is it possible to classify these substances as elements or

compounds?

1. Identify the relevant concepts.

2. Apply concepts to this situation.

Blue-green solid + black solid

heat

Symbols and Formulas

Chemists use chemical symbols to represent elements

and use chemical formulas to represent compounds.

Au O Zn

Symbols and Latin Names

Antimony

Cu

Ag

Fe

Sn

Gold

Lead

Chemical Formulas

H2O Symbol for

hydrogen

Symbol for

oxygen

Subscript for

hydrogen

C12H22O11

Symbol for

carbon

Subscript

for carbon Symbol for

hydrogen

Subscript for

hydrogen

Subscript

for oxygen

Symbol for

oxygen

Periodic Table

Groups or Families - vertical columns of elements in the periodic table. Numbered 1-18 OR with A/B system

Periods - horizontal rows of elements in the periodic table. Numbered 1-7

Ex. Ge is located in group _____ and period _____

The Periodic Table

Elements are separated into groups based on a set of

repeating properties.

Metals and Nonmetals

The periodic table is divided into two

main sections: Metals and Nonmetals

Metals –

elements that are: Ex. Cu, Ni, Al

good conductors of electricity and heat

solids at room temp with luster

ductile (drawn into wires)

malleable (hammered into sheets)

tensile strength (resist breaking when pulled)

Nonmetals

elements that are :

Poor conductors of heat and electricity

Many gases

Brittle

Ex. C, O, S

Metalloids

Elements with characteristics of both

metals and nonmetals

Ex. Si conducts electricity at high temp, not

low temp; used as a semiconductor for

computers

Noble Gases

Noble Gases- elements in Grp 18 (8A)

that are generally nonreactive

Ex. He, Ne, Ar

Section Review p. 24

Separating Mixtures

1. Filtration-for heterogeneous mixtures

made of solids and liquids

Technique that uses a barrier to separate

Mixture is poured through a piece of filter

paper. The liquid passes through leaving

the solids trapped on the filter paper.

Filtration

2. Distillation

for homogeneous mixtures

Separation technique that is based on the

boiling point of the substance

See diagram:

Distillation

3. Crystallization

Separation technique that results in the

formation of pure solid particles of a

substance from a solution containing the

dissolved substance.

When the substance contains as much

dissolved substance as it can possible hold,

the addition of a tiny amount more causes

the dissolved substance to come out of

solution and collect crystals

4. Chromatography

Separation technique that separates the

components of a mixture by solubility

Separated on the basis of the tendency of

each to travel across the surface of another

material