Chem Notes

Question 1

What is chemistry?

Answer 1

the study of composition, properties, and interactions of matter, i.e. the study of matter

Question 2

What 4 elements did the Greeks say matter consisted of?

Answer 2

earth
air
fire
water

Question 3

what method describes how a scientist thinks?

Answer 3

scientific method

Question 4

Chemistry is based on __________ and ____________

Answer 4

observation and experimentation

Question 5

hypothesis

Answer 5

tentative explanation of observations (educated guess)

Question 6

Theory

Answer 6

well sustained, comprehensive, testable explanation of a particular aspect of nature

Question 7

Law

Answer 7

theory tested over long periods of time (fleshed out theory)

Question 8

give an example of how a law can predict the future?

Answer 8

the law of gravity predicts that if you drop something it will fall to the ground

Question 9

phlogiston?

Answer 9

part of a theory from the 1600s, was believed that everything contained phlogiston and that if you burn wood the ash is what’s left over after phlogiston is taken out

Question 10

restricted law

Answer 10

is not false, but has a narrower scope

Question 11

3 areas of data

Answer 11

1. macroscopic domain
2. microscopic domain
3. symbolic domain

Question 12

macroscopic domain

Answer 12

everyday things large enough to be sensed directly

Question 13

microscopic domain

Answer 13

something we can see indirectly

Question 14

symbolic domain

Answer 14

specialized language to represent components of macro and micro domains such as chemical symbols

Question 15

matter

Answer 15

anything that takes up space and has mass

Question 16

3 states matter

Answer 16

1. solid
2. liquid
3. gas
4. plasma (newer)

Question 17

solid

Answer 17

has a definite shape and volume

Question 18

liquid

Answer 18

takes the shape of its container but has a fixed volume

Question 19

gas

Answer 19

takes the shape and volume of its container

Question 20

plasma

Answer 20

gas of highly energized ions that is difficult to containerize

Question 21

mass

Answer 21

measure of amount of matter in an object (how much there is?)

Question 22

weight

Answer 22

measurement of mass against a force

Question 23

4 groups of matter

Answer 23

1. heterogenous mixtures
2. homogenous mixtures
3. elements
4. compounds

Question 24

mixtures…

Answer 24

can always be separated

Answer 25

1. mixtures | 2. pure substances

Question 26

mixture

Answer 26

composed of 2 or more types of matter present in varying amounts

Question 27

homogenous

Answer 27

uniform composition, visually the same

Question 28

pure substance

Answer 28

comprised of one/more types of matter present in varying amounts; cannot be separated by physical changes

Question 29

element

Answer 29

cannot be broken down into simpler substance by chemical change

Question 30

compounds

Answer 30

combinations of elements

Question 31

atom

Answer 31

smallest particle of an element that has properties of that element and can enter into chemical combinations

Question 32

molecule

Answer 32

compound, 2/more atoms connected by bonds

Question 33

law of conservation of matter

Answer 33

no change total quantity of matter present when matter converts from 1 type to another

Question 34

4 types of properties

Answer 34

1. physical 2. chemical property 3. extensive property 4. intensive property

Question 35

properties

Answer 35

characteristic enables us to distinguish

Question 36

physical property

Answer 36

what things look like; characteristic not association with change in chemical composition

Question 37

physical property examples

Answer 37

density, hardness, melting and boiling points, conductivity

Question 38

physical change

Answer 38

change in state/property of matter without accompanying change in its chemical composition

Question 39

chemical property

Answer 39

can't usually see it; association with chemical composition

Question 40

chemical change

Answer 40

change in chemical properties of matter by changes in chemical composition

Question 41

reaction

Answer 41

way of measuring chemical changes

Question 42

extensive property

Answer 42

depends on amount of matter present (mass, volume, heat)

Question 43

intensive property

Answer 43

does not depend on amount of matter present (density, temperature)

Question 44

density is inversely related to what?

Answer 44

volume

Question 45

3 parts of a number

Answer 45

1. size/ magnitude of measurement 2. the unit 3. indication of uncertainty

Question 46

unit

Answer 46

standard for comparison for the measurement

Question 47

2 formats for expressing numbers

Answer 47

1. decimals | 2. scientific notation

Question 48

SI unit for length

Answer 48

meter

Question 49

SI unit for math

Answer 49

kilogram kg

Question 50

SI unit for time

Answer 50

second s

Question 51

SI unit for temperature

Answer 51

Kelvin K

Question 52

SI unit for electric current

Answer 52

ampere A

Question 53

Kelvin does not have degrees because it is an...

Answer 53

absolute temperature scale

Question 54

derived units

Answer 54

formed from SI base units

Question 55

volume

Answer 55

measure of amount of space an object occupies

Question 56

standard SI unit for volume

Answer 56

cubic meter

Question 57

density

Answer 57

physical property relating the ratio of the mass of a sample to its volume

Question 58

SI unit for density

Answer 58

kilogram per cubic meter kg/m^3

Question 59

compound unit

Answer 59

combination of several smaller units put together

Question 60

give an example of a compound unit

Answer 60

density

Question 61

2 types of numbers

Answer 61

1. exact numbers | 2. certain/uncertain digits

Question 62

certain digits

Answer 62

are measured by comparing to an actual size

Question 63

uncertain digits

Answer 63

digits that are guessed

Question 64

figures that are significant

Answer 64

1. nonzero digits 2. captive zeros 3. trailing zeros (if to the right of decimal place)

Question 65

non significant figures

Answer 65

1. leading zeros | 2. trailing zeros (when to the left side of decimal place

Question 66

accurate

Answer 66

if it yields a result that is very close to the true or accepted value

Question 67

precise

Answer 67

if it yields very similar results when repeated

Question 68

percent error is a measure of..

Answer 68

measure of the accuracy

Question 69

when adding or subtracting...

Answer 69

you take the least number of significant digits

Question 70

when multiplying/dividing

Answer 70

you take the least amount of sig figs

Question 71

density

Answer 71

ratio of mass of an object to its volume

Question 72

how can you measure mass

Answer 72

place object on a balance

Question 73

2 different ways to measure volume

Answer 73

1. equation if a geometric solid -> v=a^3 | 2. water displacement

Question 74

dimensional analysis

Answer 74

based on the premise that the units of quantities must be subjected to the same mathematical operations as their associated conversion factors; ratio fo two equivalent quantities expressed with different units