chapter 2: matter and change 2.1 matter. i. properties of matter a. substance: matter with uniform...

Chapter 2: Matter and Change

2.1 Matter

I. Properties of Matter• A. Substance: matter with uniform and definite

composition

• Write down 3 examples.

Which of the following is NOT a substance?

Pure Gold (Au) Dry Ice (Solid Carbon Dioxide) (CO2)Milk

• B. Physical Property: condition of substance observed without changing composition

• Write down 3 examples for the object below.

Gallium (Ga)

II. States of Matter• A. Solid: definite shape

and volume, tightly packed particles

• B. Liquid: fixed volume, takes shape of container

• C. Gas: takes shape and volume of container

III. Physical Changes• A. Altering a material without changing

composition• Write down which physical change is

described in each picture.

2.2 Mixtures

I. Classifying Mixtures• A. Mixture: physical combination of 2 or more

substances

1. Can be consistent (Homogeneous) or different composition throughout (Heterogeneous)

Are these mixtures homogeneous or heterogeneous?

• B. Solution: a homogeneous mixture, can be solids, liquids, or gases

• C. Phase: any part of mixture that is consistent

Oil and water heterogeneous mixture has two phases

II. Separating Mixtures• A. Distillation: separating a mixture by boiling

liquid to vapor and then returning to liquid• B. Chromatography: separating substances by

their mass

2.3 Elements and Compounds

Hemoglobin Molecule

I. Element vs. Compound• A. Element: simplest naturally existing form of

matter (periodic table)

• B. Compound: two or more different elements combined

Label these as: elements, compounds, or mixtures?

• C. Compounds only separated by chemical means

Ex. Sugar Caramel Carbon + water vapor

• D. Properties of compounds different than partsEx. Sodium (reactive metal) + Chlorine gas (poisonous) Sodium Chloride (Salt)

II. Symbols and Formulas• A. Elements represented by symbols• B. Most are first one or two letters of element• C. Some represent Latin or Greek namesFind 4 elements that have symbols that are

NOT their first one or two letters.

2.4 Chemical Reactions

I. Reactants to Products• A. Chemical Reaction: one or more

substances become new substances

Iron + Oxygen Iron Oxide (Rust)

Reactants Product

II. Detecting a Chemical Reaction• A. Chemical Property/Change: undergoes

chemical rxn to form new substances

Ex. Rusting, burning, exploding, fermenting

• B. Chemical rxns always give off or absorb energy (temp. change or light)

• C. Other signs: Color, Odor, Precipitate (solid that settles out of liquid mixture)

III. Conservation of Mass• A. During any chemical reaction, the amount of

matter is unchanged