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Flashcards in Unit 2 Deck (103):
1

Temperature

Average kinetic energy per molecule (speed pee molecule)

2

Heat

Flow of thermal emergency from hot to cold
(Flow of kinetic energy from one molecule to another)

3

First law of thermodynamics

Energy can't be created or destroyed only converted or transferred from one form/place to another

4

Rule two of thermodynamics

Heat energy flows from high temperature to low temperature areas only

5

Thermal equilibrium

No net flow of heat emergency because all areas are same temperature
(Putting in as much as taking out)
Passes back equally

6

How does a thermometer work

Molecules of alcohol speed up and expand or slow down and contract

7

What causes the red line I a thermometer to stop moving

Thermal equilibrium between thermometer and water causes it to stop moving

8

What is temperature measured in

Celsius, C

9

What is heat measures in

cal. c.

10

What is one calorie

The amount of heat needed to raise the temp of one military of water
1 ml H2O by 1 degree

11

What are the calories in your food

Calories, actually kilocalories
(Amount of heat needed to warm up 1,000 ml of water by one degree)

12

High specific heat

More heat energy needed to increase the temp of some substances

13

Thermal energy

Total energy in molecules of a substance
A) kinetic energy of movie molecules
b) potential energy stored in chemical bonds

14

What cases phase change

Heat transfer

15

Phase change:

Change in amount of thermal energy cause molecules to move in different ways

16

Higher energy

Weaker intermolecular forces, mass does not change but density does

17

Conduction

Objects touch, direct heat transfer molecule to molecule

18

Convection

Heat transferred by flowing molecules
Warm fast moving molecules rise carrying heat with them, they expand and become less dense

19

Radiation

Electromagnetic waves , infrared radiation, no molecules

20

What direction does heat energy always flow and what law

Law of thermodynamics
Heat energy flows from high temperature to low temperature areas only

21

What is absolute 0

No motion of particles
0 Calvin

22

Why are metals good conductors

Because the electrons are loosely held (can flow)

23

Why are non metals poor conductors

Hold their electrons tightly so are poor conductors

24

Why do good conductors feel cold

At room temp feel cold evaluate heat is leaving your body quickly

25

Why are poor conductors not as cold

Because heat is leaving slower

26

If an object has a high specific heat capacity

It takes longer to heat up

27

Sublimation

Solid to gas

28

Deposition

Gas to solid

29

Gas to liquid

Condensation

30

Liquid to gas

Vaporization

31

Solid to liquid

Melting

32

Liquid to solid

Freezing

33

Solids

Vibrate in place and are closely compacted

34

Liquid

Particles can flow
Are spread out

35

Gas

Particles can flow and expand
Distance is big between particles

36

Where is the phase change on a graph

When it goes horizontal

37

Potential energy is: on a graph

The horizontal parts

38

Kinetic energy is: on a graph

The climbing parts /

39

Where is condensation in a graph

Where there is boiling

40

Where is crystallization on a graph

Where there is melting

41

The higher energy ----- the intermolecular forces

Lower intermolecular forces

42

What has lowest to highest energy

Solid lowest, liquids medium, gases highest

43

Weaker intermolecular forces means molecules can

Flow and spread apart

44

Chemical change

When chemical bonds are made or broken and new substances are formed

45

Example of chemical change

Burning ( combustion, flammability) rusting, tarnishing

46

Physical change

Change That does not break or form any chemical bonds, no new substances formed

47

Physical change examples

Phase change (melting, boiling etc) change in shape, change in size, mixtures, dissolving

48

Chemical property

Chemical properties indicate what types of chemical change a substance can do
Ex. Flammability

49

Physical property

Describe the physical characteristics of a substance
Ex. Density, melting point, solubility

50

What is the goal when balancing equations

The goal is to get the same number of atoms of each element on each side of the yield arrow

51

What happens to atoms in a chemical reaction

They break old bonds and form new ones

52

Acid or base
Starts with h

Acid

53

Acid or base
Donates protons

Acid

54

Acid or base
Blue litmus color change to red

Acid

55

Acid or base
Starts with oh

Base

56

Acid or base
Accepts protons

Bases

57

Acid or base
Greater than 7 ph range

Base

58

Acid or base
Phenolphthalein paper color change

Bases
Pink and purple

59

Acid or base
Oh range less than 7

Acid

60

When acid and a base react what are the two products

Always some type of salt and water

61

What is the same for the reaction that happens between an acid and a base

Neutralization reactions

62

Acid or base
HCL

Acid

63

Acid or base
NaCl

Neither

64

Acid or base
NaOH

Base

65

Acid or base
H2SO4

Acid

66

H2O

Neither

67

What is an isomer

Two molecules that have the exact same chemical formula but have different order of atoms

68

What is a polymer

A very large molecule (macromolecule) that is made by putting together a bunch of smaller molecules (monomer)

69

Examples of polymers found in your body

DNA, proteins, and carbohydrates

70

What is a hydrocarbon

a hydrocarbon are organic molecules that contain only hydrogen and carbon, no other elements

71

List the number of carbons
Butane

4

72

List the number of carbons
Octane

8

73

List the number of carbons
Pentane

5

74

List the number of carbons
Methane

1

75

List the number of carbons
Propane

3

76

List the number of carbons
Ethane

2

77

List the number of carbons
Heptane

7

78

List the number of carbons
Hexane

6

79

What is the difference between a straight chain molecule of butane and its isomer and what's the same

They have different shapes and different properties
They have the same chemical formula

80

Draw the structure of a carboxylic acid

.....O
.....||
.....C--OH

81

Alpha particle

Two protons and two neutrons

82

Beta particle

One electron

83

Gamma radiation

Pure energy

84

Half life

The amount of time it takes for half of a radioactive substance to decay

85

Radioactive

Giving off radiation (alpha particles, beta particles, and or gamma together)

86

Strong nuclear force

Attractive force between nucleons, holds the nucleus together

87

Electromagnetic force

Force of attraction between electrons and protons force of repulsion between protons

88

Transmutation

One element mutates into a different element by giving off a radioactive particle

89

What is more radioactive a shorter or longer half life and why

Shorter half life because it is more radioactive, it is giving off radioactive particles faster

90

How does the atomic number and atomic mass change when an alpha particle is shot off

Atomic number goes down by two because two protons are shot off, atomic mass goes down by four because two protons and two neutrons

91

How does the atomic mass and atomic number change when a beta particle is shot off

The atomic number does up by one because a neutron is converted into a proton and the atomic mass stays the same

92

Compare and contrast the strong nuclear force with the electromagnetic force

Strong nuclear force: short range, works on protons and neutrons, stronger
Electromagnetic force: long range, works on protons and electrons (only charged particles), and is weaker

93

What problems occur when exposed to radioactive decay for long periods of time at high levels

Cancer, birth defects m, shortened life span

94

Chain reaction

Splitting one atom causes several atoms to split when neutrons are shot off

95

Critical mass

Mass of enriched uranium needed to start an explosion

96

Nuclear fusion

Two small atoms fuse together

97

Nuclear fission

A large atom splits in two

98

Thermonuclear fusion

Fusion that takes place at very high temps

99

Why do some atoms split but others don't

Only atoms of uranium 235 split and in high concentrations

100

Under what conditions can nuclear fusion happen

Very high temps

101

Fusion

Fuse no pollution

102

Thermonuclear fusion

Very high temps

103

Fission

Splits, radioactive waste, cooler temps