science chemistry test review

Seite 1

Chemistry

test review ( summary)

DEFINE

MIXTURE

: a substance made by mixing other substances together.

PURE

SUBSTANCE: Pure substance are made

of only one type of atom or molecule, and the purity of a substance is the

measure of the extent to which a given substance is pure. The physical

properties of a pure substance include

well-defined melting and boiling points.

Ice melts : physical change

Wood burns: chemical change

A glass breaks: physical

change

A snowflake forms: physical

change

DEFINE

SOLUTION

:

the process by which a gas, liquid, or solid is dispersed

homogeneously in a gas, liquid, or solid without chemical change.

MECHANICAL MIXTURE : a mixture whose components can be separated by mechanical means mixture is a substance consisting of two or more substances mixed together (not in fixed

proportions and not with chemical bonding)

Pure sugar : solution

Salt dissolve in water :

mechanical mixture

Iron filings and sugar :

mechanical mixture

Marble and stones: mechanical

mixture

PHYSICAL PROPERTY : a

characteristic of matter that can be observed with senses or measured

CHEMICAL PROPERTY : a substances ability to change into a

whole new substance

CHMEICAL CHANGE : any changes in matter that creates a new substance

"messing with the formula"

PHYSICAL CHANGE : A change in size, shape, or state without forming a new

substance

texture : physical property

Odour : chemical property

Reaction with acid :

chemical property

Clarity : chemical property

QUALITATIVE OBSERVATION

: a non-numerical observation that

describes the qualities of objects or events

QUANTILITATIVE OBSERVATION

: a numerical observation based on

measurements or counting

6

B)

Qualitative observation

Quantilitative observation

Qualitative observation

Quantilitative observation

Characteristic physical

property : a

property that is unique to a substance and that can be used to identify

7

B )

Melting point :

Characteristic physical property

Boling point : Characteristic

physical property

Density : Characteristic

physical property

Lustre : is not

Characteristic physical property

Element : a pure substance that cannot be

broken down into simpler substance either physically or chemically

Compound : a pure substance

made up of two or more element that

are chemically joined

Q10

A ) Moth balls sublimate into air PHYSICAL CHANGE

B )

iron rust on a car PHYSICAL CHANGE

C ) wood is chopped into a little pieces PHYSICAL CHANGE

D ) glasses is shattered with a hammer PHYSICAL CHANGE

-a substance disappears.

-a solid is formed.

-a colour change occurs.

-a new odour is produced.

-a change of form (for example, burning paper).