Chapter 1: An Atoms Focused Approach

Question 1

Atom

Answer 1

The smallest particle of an element that cannot be chemically or mechanically divided into smaller particles.

Question 2

What is Scientific theory?

Answer 2

A concise, extensively tested explanation of widely observed natural phenomena.

Question 3

Element

Answer 3

A pure substance that cannot be separated into simpler substances.

Question 4

Compound

Answer 4

A pure substance composed of two or more elements that are chemically bonded in fixed proportion.

Question 5

What is scientific methods?

Answer 5

Approaches to acquiring knowledge by observing phenomena, developing a testable hypothesis, and carrying out additional experiments that test the validity of the hypothesis.

Question 6

Scientific law

Answer 6

A concise and generally applicable statement of a fundamental scientific principle.

Question 7

Law of definite proportions

Answer 7

The principle that a compound always contains the same proportion of its component elements.

Question 8

Law of constant composition

Answer 8

The principle that all samplers of a given compound have the same elemental composition.

States that a compound always has the same elemental composition by mass no matter what its source.

Question 9

Hypothesis

Answer 9

A tentative and testable explanation for an observation or a series of observations.

Question 10

Law of multiple proportions

Answer 10

The principle that, when two masses of one element react with a given mass of another element to form two compounds, the two masses of the first element have a ratio of two small whole numbers. EX: 15g oxygen/ 10g oxygen = 3/2

Question 11

Chemical formula

Answer 11

A notation that uses the symbols of the elements to represent the elemental composition of a pure substance; subscripts indicate the relative number of atoms of each element in the substance.

Question 12

COAST

Answer 12

Collect and Organize-
Analyze-
Solve-
Think about it-

Question 13

Matter

Answer 13

Anything that has mass and occupies space.

Question 14

Mass

Answer 14

The property that defines the quantity of matter in an object

Question 15

Chemistry

Answer 15

The study of the composition, structure, and properties of matter and of the energy consumed or given off when matter undergoes a change.

Question 16

Pure substance

Answer 16

Matter that has a constant composition and cannot be broken down to simpler matter by any physical process.

Question 17

Physical process

Answer 17

A transformation of a sample of matter, such as a change in its physical state, that does not alter the chemical identity of any substance in the sample; also called physical change

Question 18

Intensive property

Answer 18

A property that is independent of the amount of substance

Question 19

Extensive property

Answer 19

A property that varies with the amount of substance

Question 20

Physical properties

Answer 20

A property of a substance that can be observed without changing the substance into another substance.

Question 21

Density

Answer 21

The ratio of the mass, of an object to its volume.

Question 22

Density equation

Answer 22

D=m / v

Question 23

Chemical reactions

Answer 23

The conversation of one or more substance into one or more different substances; also called chemical change.

Question 24

Chemical property

Answer 24

A property of a substance that can be observed only by reacting the substance with something else to form another substance

Question 25

Chemical bonds

Answer 25

A force that holds two atoms or ions in a molecule or a compound together

Question 26

Molecules

Answer 26

A collection of chemically bonded atoms. Meaning they have no net electrical charge.

Question 27

Ions

Answer 27

A particle consisting of one or more atoms that has a net positive or negative charge

Question 28

Mixture

Answer 28

A combination of pure substance in various proportions in which the individual substances retain their chemical identities and can be separated from one another by a physical process.

Question 29

Homogeneous mixture

Answer 29

A mixture in which the components are distributed uniformly and the composition and appearance are uniform.

Question 30

Solutions

Answer 30

Another name for a homogeneous mixture. Solutions are often liquids, but they may also be solids or gases.

Question 31

Heterogeneous mixture

Answer 31

A mixture in which the components are not distributed uniformly, so that the mixture contains regions of different compositions.

Question 32

Immiscible liquids

Answer 32

Combinations of liquids that do not mix with, or dissolve in, each other.

Question 33

Distillation

Answer 33

A process using evaporation and condensation to separate a mixture of substances with different volatilities

Question 34

Volatility

Answer 34

A measure of how readily a substance vaporizes

Question 35

Filtration

Answer 35

A process for separating solid particles from a liquid or gaseous sample by passing the sample through a porous material that retains the solid particles.

Question 36

Chromatography

Answer 36

A process involving a stationary and a mobile phase for separating a mixture of substances according to their different affinities for the two phases.