Unit 6

Question 1

renewable energy sources

Answer 1

can be replenished naturally, or at a near rate of consumption and reused

Question 2

nonrenewable energy sources

Answer 2

exist in fixed amounts on earth and can’t be replaced or regenerated

Question 3

fossil fuels

Answer 3

the most common fuel source globally (oil, coal, natural gas)

Question 4

hydroelectric energy

Answer 4

dams used to create energy; water spins a turbine, which generates electricity

Question 5

nuclear

Answer 5

uranium fission releases heat to turn water into steam to turn a turbine to generate electricity

Question 6

subsistence fuels

Answer 6

biomass that can be easily gathered/purchased by people in less developed countries (wood, charcoal, dried animal manure)

Question 7

coal formation

Answer 7

pressure from overlying rock and sediment layers compacts peat into coal over time

Question 8

natural gas

Answer 8

decaying remains of plants and animals (marine life) are buried under layers of rock and converted by pressure into oil (petroleum) and natural gas over time

Question 9

crude oil (petroleum)

Answer 9

decaying organic matter trapped under rock layers is compressed into oil over time (extracted by drilling a well that pumps out liquid oil)

Question 10

bitumen

Answer 10

thick, semi-solid form of petroleum (not liquid)

Question 11

hydraulic fracturing (fracking)

Answer 11

a method of natural gas extraction that has extended access to natural gas

Question 12

tar/oil sands

Answer 12

bitumen deposits where crude oil can be recovered with higher water and energy inputs

Question 13

fossil fuel combustion

Answer 13

reaction between oxygen (O2) and fossil fuels (hydrocarbons) that releases energy as heat and produces CO2 and H2O as products

Question 14

cogeneration

Answer 14

when the heat produced from electricity generation is used to provide heat (air and hot water) to a building

Question 15

nuclear fission

Answer 15

a neutron is fired into the nucleus of a radioactive (unstable) element such as Uranium

Question 16

radioactivity

Answer 16

the energy given off by the nucleus of a radioactive isotope

Question 17

radioactive half-life

Answer 17

the amount it takes for 50% of a radioactive substance to decay

Question 18

nuclear meltdowns

Answer 18

• Three Mile Island
• Fukushima
• Chernobyl

Question 19

biomass

Answer 19

organic matter (wood/charcoal, dried animal waste, dead leaves/brush) burned to release heat to heat homes and cooking

Question 20

biofuels

Answer 20

liquid fuels (ethanol, biodiesel) CREATED FROM biomass (corn, sugar cane, palm oil)

Question 21

modern carbon

Answer 21

CO2 that was recently sequestered (taken out of the atmosphere)

Question 22

biodiesel

Answer 22

liquid fuels produced specifically from plant oils (soy, canola, palm)

Question 23

passive solar energy

Answer 23

absorbing or blocking heat from the sun without use of mechanical/electrical equipment

Question 24

active solar energy

Answer 24

use of mechanical/electrical equipment to capture sun’s heat (solar water heaters or concentrated solar thermal) or convert light rays directly into electricity (PV cells)

Question 25

photovoltaic cells (PV)

Answer 25

solar panels; emits a low voltage electrical current when exposed to the sun

Question 26

concentrated solar thermal (CST)

Answer 26

heliostats (mirrors) reflect sun's rays onto a central water tower in order to heat water to produce steam to turn a turbine into electricity

Question 27

hydroelectricity: how it works

Answer 27

kinetic energy of moving water spins a turbine and the turbine powers a generator

Question 28

tidal power

Answer 28

comes from tidal ocean flow which turns a turbine (coastal areas only)

Question 29

fish ladders

Answer 29

cement steps or series of pools that migratory fish like salmon can use to continue migration upstream around or over dams

Question 30

geothermal energy

Answer 30

naturally heated water reservoirs underground are drilled into and piped up to the surface (or water can be piped down into naturally heated rock layers) and converted to steam, which powers a turbine and generates electricity

Question 31

hydrogen fuel cell basics

Answer 31

uses hydrogen as a renewable, alternative fuel source to fossil fuels