Chapter 1

Question 1

Chemistry

Answer 1

The study of matter and the changes it undergoes ( central science)

Question 2

Scientific method

Answer 2

A systematic approach to research

Observation—>representation——> interpretation—> back to observation

Question 3

Hypothesis

Answer 3

A tentative exclamation for a set of observation ( educated guess)

Question 4

Law

Answer 4

A concise statement of a relationship between phenomena that is always the same under the same condition.

Question 5

Theory

Answer 5

A uniting principle that explains the body of facts and/or those laws that are based on them

Question 6

Classification of matter

Answer 6

Matter 
Substance 
Elements 
Compounds
Mixture

Question 7

Matter

Answer 7

Anything that occupies space and has mass

Question 8

Substance

Answer 8

A term of matter that has a definite (constract) composition and distinct properties.

Question 9

Elements

Answer 9

A substance that cannot be separated into simpler substances by chemical methods ( periodic table)

Example : hydrogen/ Oxygen

Question 10

Compounds

Answer 10

Composed of Atoms of two or more elements chemically united in fixed proportions;can only be separated into elements by chemical means

Example: Sand with iron fillings and oil and water.

Question 11

Mixture

Answer 11

Combination of two or more substances in which they retain their distinct identities and they can be separated into pure components by physical means

Example: Evaporating water to see the left over salt

Question 12

Homogeneous mixtures

Answer 12

The composition of the mixture is the same throughout.

Example: sugar resolving in water, air

Question 13

Heterogeneous mixture

Answer 13

The composition of the mixture is not uniform.

Example; sand with iron fillings, oil and water.

Question 14

States of matter

Answer 14

Solid
Liquid
Gas

Question 15

Solid

Answer 15

Particles are held close together (atoms, molecules, Ions) in And orderly fashion with a little freedom of motion

Question 16

Liquid

Answer 16

Particles are Close together but can you past each other

Question 17

Gas

Answer 17

Particles are separated by distance that are large composed to their size

Question 18

Fusion
(Melting). Vaporization
Solid liquid gas
Freezing. Condensation

Answer 18

Know this

Question 19

Physical property

Answer 19

Can be measured in observed without changing composition or identity of the substance

Question 20

Chemical property

Answer 20

Observed by changing out a chemical change which alters the composition or identity of the substance involved

Question 21

Extensive property

Answer 21

Depends on how much matter is being considered

example:mass,length,and volume

Question 22

Intensive property

Answer 22

Does not depend on how much matter is being considered

Example: Density temperature and color

Question 23

Macroscopic property

Answer 23

Can be determined directly

Question 24

Microscopic property

Answer 24

On the atomic or molecular scale must be determined by indirect methods

Question 25

SI units

Answer 25

International system of units

Question 26

``` Best quantity Length (L) mass (m) time (t) electrical current (I) temperature (T) amount (n) ```

Answer 26

``` Name of unit Meter (m) kilogram (kg) seconds (s) ampere (A) Kelvin (k) Mole (mol) ```

Question 27

Mass (m)

Answer 27

Measure of the quantity of matter - different from weight - The SI units is KG (1 kg =10^3g=1000g)

Question 28

Volume (v)

Answer 28

How much space matter takes up - SI unit derived unit is cubic meter (m^3) -commonly used unit is liter( L) where 1L=1000 mL = 1000 cm^3 =1dm^3 & 1 mL=1 cm^3

Question 29

Density formula

Answer 29

D= m/v | Mass/ volume

Question 30

Scientific notation

Answer 30

System of handling numbers that are very large or very small or numbers of atoms in 12 G of carbon

Question 31

Significant figures

Answer 31

The meaning digits in a measured or calculated quantity used to indicate the Margin of error ( last digits is understood to be uncertain)

Question 32

Exact numbers

Answer 32

Numbers from definitions of numbers of objects are considered to be an infinite number of significant figures

Question 33

Accuracy

Answer 33

How close a measurement is to the true value

Question 34

Precision

Answer 34

How close is that of measurement are to each other

Question 35

Dimensional analysis

Answer 35

Method to convert between units in solving chemistry problems based on the relationship between different units that express the same physical quantity

Question 36

Mega (M)

Answer 36

10^6 | 1Mm= 10^6m

Question 37

Kilo( k)

Answer 37

10^3 1 km = 10^3 m

Question 38

Deci (d)

Answer 38

10^-1 | 1 dm= 10^-1m

Question 39

Centi (c)

Answer 39

10^-2 | 1 cm= 10^-2m

Question 40

Milli ( m)

Answer 40

10^-3 | 1mm=10^-3m

Question 41

Micro( fancy m)

Answer 41

10^-6 1mm= 10^-6m

Question 42

Neno ( n)

Answer 42

10^-9 1nm=10^-9m

Question 43

Pico (p)

Answer 43

10^-12 1 pm= 10^-12m

Question 44

Femto (f)

Answer 44

10^-15 1fm= 10^-15 m