Chapter 2-1

Mixture

A combination of substances that are not chemically combined; can be separated

Conversion Factor

A fraction used to convert units. The numerator contains the units you want and the denominator contains the units you have. The numerator of the fraction = the denominator's measurement but in different units.

Volume

A measure of the size of a body or region in three-dimensional space

What is the difference between a pure substance and a mixture?

A mixture can be physically separated into its parts. The parts of a pure substance are chemically combined and cannot be physically separated.

Alloy

A mixture of two or more metals

Compound

A substance made up of atoms of different elements and cannot be separated

Element

A substance that cannot be broken down into simpler substances by chemical means

What can atoms that make up a molecule do?

Act as a unit

Mass

Amount of matter in an object.

Matter

Anything that has mass and takes up space

What do chemical formulas represent?

Compounds

What are the two types of Pure substances?

Compounds (molecules/formula unit) and Elements (atoms)

Whats the relationship between elements and atoms?

Each element is made of one kind of atom.

How are elements related to compounds?

Each molecule of a compound contains two or more elements that are chemically combined.

Compare mixtures and substances

Elements and compounds are pure substances, but mixtures are not.

Why do compounds have unique properties?

Every compound differs from the elements that it contains.

How can matter be classified?

Every sample of matter is either an element, a compound, or a mixture.

What are the two types of mixtures?

Heterogeneous (suspensions) and homogeneous (solutions)

How are mixtures classified/defined?

How well the substances mix.

Pure substance and examples

Matter that has a fixed composition and definite properties. Ex: tin, sulfur, diamond, water,

Compare miscible and immiscible and give examples

Miscible is when liquids are able to be mixed (ex. liquids in gasoline). Immiscible are liquids that don't mix (ex. water and oil).

All mixtures are solutions because.....

Mixtures are one or more substance that combined to create a solution

Molecules that are made of atoms of the same element

Neon: 1, Hydrogen: 2, Oxygen: 2, Chlorine: 2, Phosphorus: 4

Elements that make up the Human Body

Sulfur 0.2%, Nitrogen 2.4%, Others 1%, Oxygen 65%, Sodium 0.3%, Calcium 1.6%, Potassium 0.4%, Hydrogen 10.2%, Phosphorus 0.9%, Carbon 17.5%

What are elements represented by?

Symbols

Independent Variable

The experimental factor that is manipulated; the variable whose effect is being studied. X-axis.

Dependent Variable

The outcome factor; the variable that may change in response to manipulations of the independent variable. Y-axis

Atom

The smallest unit of an element that keeps the element's chemical properties

Molecule

The smallest unit of matter of a substance that retains all the physical and chemical properties of that substance

Compare heterogeneous and homogeneous mixtures and examples.

The substances in a heterogeneous mixture are not evenly distributed (ex. salad). In a homogeneous mixture, the components are evenly distributed (ex. vinegar).

Why are carbon and copper classified as elements?

They cannot be broken down into simpler substances by chemical means.

A water molecule is an example of a compound...

Two Hydrogen, one Oxygen

Why it Matters

Understanding matter helps you understand your world.