Unit 7

Question 1

The first law of thermodynamics

Answer 1

Shares that energy can neither be created nor destroyed, only transformed between forms, this means chemical reactions involve a transfer of heat

Question 2

The second law of thermodynamics

Answer 2

The second law of thermodynamics states that processes that involve the transfer or conversion of heat energy are irreversible and always move toward more disorder.
States that the entropy of a system will increase (the disorder of energy in a process should increase)

Question 3

System

Answer 3

All of the reactants and products

Question 4

Surroudinings

Answer 4

All things that contain and interact with the system

Question 5

System + surroundings=

Answer 5

Universe

Question 6

Endothermic reaction

Answer 6

Heat flows into the system from the surroundings
Heat of reaction can be written in as one of the reactants
Change of heat is a positive value
Surroundings get colder

Question 7

Exothermic reaction

Answer 7

Heat flows out of a system and into the surroundings
Heat of a reaction can be written in as one of the products
Change of heat is a negative value
Surroundings get hotter

Question 8

Melting

Answer 8

A solid changes into a liquid
Endothermic reactions (gain of heat)

Question 9

Melting point

Answer 9

The temperature at which a solid turns into a liquid

Question 10

Evaporation

Answer 10

A liquid changing into a gas
Endothermic reaction (gain of heat)

Question 11

Boiling point

Answer 11

The temperature at which a liquid turns into a gas

Question 12

Sublimation

Answer 12

A solid changing directly into a gas
Endothermic reaction (gained heat)

Question 13

Freezing

Answer 13

A liquid changing into a solid
Exothermic reaction (Losing heat/getting colder)

Question 14

Freezing point

Answer 14

The temperature at which a liquid turns solid

Question 15

Condensation

Answer 15

A gas turns into a liquid
Exothermic reaction (losing heat/getting colder)

Question 16

Condensation point

Answer 16

The temperature at which a gas turns into a liquid

Question 17

Disposition

Answer 17

A gas turning into a solid
Exothermic reaction (Losing heat/getting cold)

Question 18

Heating curves

Answer 18

A heating curve shows temperature increase as heat is added to a substance
Heating curves begin with a solid and progress to a gas
Positive correlation between time and temperature

Question 19

Cooling curves

Answer 19

A cooling curve shows temperature decrease as heat is removed from a substance
Cooling curves begins with a gas and ends at a solid
Negative correlation between temperature and time

Question 20

Reading heating and cooling curves

Answer 20

Diagonal lines indicate a state of matter changing temperature
Horizontal lines indicate a phase change

Question 21

Thermodynamics

Answer 21

The science of the relationship between heat and temperature and now they influence energy and the ability to do work

Question 22

Specific heat capacity

Answer 22

The amount of heat required to change the temperature of 1 gram of a substance up 1 degree celsius

Question 23

Heat

Answer 23

The transfer of thermal energy between molecules

Question 24

Temperature

Answer 24

A measure of the average kinetic energy of molecules in a substance

Question 25

Calorimetry

Answer 25

A process that measures the heat of a reaction for various reasons and processes

Question 26

The carbon cycle

Answer 26

The movement of our fixed amount of carbon between the land, atmosphere, oceans, and living organisms

Question 27

Processes that absorb CO2 from the atmosphere

Answer 27

Forests: Take in CO2 and convert it into sugar using photosynthesis, take in more carbon then they release
Oceans: Take in CO 2 via diffusion (It will reach equilibrium with the amount in the atmosphere)
Soil, plant biomass, and animal biomass: Also absorbs carbon, these organisms need cells to live so they take in carbon to make them

Question 28

Processes that release CO2 from the atmosphere

Answer 28

Cellular respiration: When plants, animals, and microbes respire they release CO2 into the cycle
Oceans: Take in CO 2 via diffusion (It will reach equilibrium with the amount in the atmosphere)
Human emissions: Production of chemicals and materials that we use, deforestation, and agriculture all release C02

Question 29

The greenhouse effect

Answer 29

Keeps Earth warm and suitable for life by trapping in heat energy, and thus keeping the temperature high and stable

Question 30

Non-renewable energy

Answer 30

Ones that cannot be replaced or re-made at a rate equal to their consumption

Question 31

Types of non-renewable energy

Answer 31

Coals, natural gas, oil, gasoline

Question 32

Nuclear energy

Answer 32

Uses nuclear fission (breaking apart the nucleus of an atom) to generate energy

Question 33

Renewable energy

Answer 33

Energy sources that can be replaced or re-made at a rate equal to or exceeding consumption

Question 34

Solar energy

Answer 34

Absorbs energy using the sun and converts it into energy we can use
Ex. solar panels
Pros: Energy can be stored in batteries, little to no land destruction
Cons: Still somewhat inefficient, expensive

Question 35

Wind energy

Answer 35

Wind turns a turbine and generates energy
Ex. Wind turbines
Pros: Fairly cheap, Efficient
Cons: Noisy, high construction, wind can’t be to fast or to slow

Question 36

Hydroelectric energy

Answer 36

Water flows through a turbine and generates energy that we can use
Ex. dams
Pros: Efficient, constant source of energy
Cons: Expensive, destroys ecosystems, floods upstream land

Question 37

Geothermal energy

Answer 37

Energy from the heat of the Earth is converted into energy that we can use
Ex. Geysers
Pros: Energy source generated by Earth; land friendly
Cons: Expensive, may cause earthquakes

Question 38

Biomass energy

Answer 38

Using crops, trash, wood, etc. that have absorbed energy from the sun and converting it into energy that we can use
Ex. Wood
Pros: Abundant, natural supply
Cons: Requires large amount of space, expensive

Question 39

How are non-renewable resources made?

Answer 39

when prehistoric plants and animals died and were gradually buried by layers of rock