Chapter 15: energy Flashcards Preview

Earth 122 > Chapter 15: energy > Flashcards

Flashcards in Chapter 15: energy Deck (38)
Loading flashcards...
1

What is the mackenzie valley gas project?

a proposal to develop three major gas fields in the mackenzie delta, NWT.

2

examples of fossil fuels?

oil , natural gas, coal, oil shale, tar sands

3

what are fuels?

energy stored in chemical bonds of ancient organic life.

4

What is electricity?

A secondary form of energy that is easier to transfer than fossil fuels

5

When are fossil fuels produced?

when organic materials are broken down in anearobic(little to no oxygen) environments. occurs at the bottom of deep lakes, swamps, and shallow seas

6

what nation has the most coal?

USA

7

Net energy =

Energy returned - energy invested

8

what is coal?

organic plant and animal matter that was compressed under very high pressure to form dense carbon structures

9

What is the least compressed and most compressed (more energy) coals called?

Lignite LLLeast compressed
Anthracite most compressed

10

how does peat differ from coal?

peat remains wet when broken down, not well compressed

11

What impurities does coal contain

sulfur, mercury, arsenic, and other tracd materials.

12

What does the sulfur content of coal depend on?

whether it was formed in saltwater or fresh water

13

what are oil and natural gas mainly formed from?

plankton, including algae and bacteria

14

What does natural gas consist of?

Methane(ch4), varying amounts of other volatile hydrocarbons

15

How much of the worlds energy is from natural gases?

25%

16

How much longer are the worlds natural gases expected to last for?

only 60 yrs

17

What is kerogen?

A precursor to oil, created at shallow depths by bacterial anearobic decomposition of organic matter

18

What is coalbed methane

methane from coal seams, leaks to atmosphere during mining

19

What is crude oil?

A mixture of hundreds of different types of hydrocarbon molecules. Formed 1.5-3 km underground from dead organic material buried in marine sediments

20

whats the mosr abundant fossil fuel?

coal

21

what is the precursor to coal?

peat

22

subsurface mining

Involves digging deep into the ground, and networks of tunnels are dug or blasted out to follow coal seams

23

strip mining

heavy machinery removes earth in long, horizontal strips to expose seams and extract coal. pits are refilled with the soil that was removed.

24

Acid drainage

when sulfide minerals in newly exposed rock surfaces react with oxygen and rain water to produce sulphuric acid. The acid runs off and leaches toxic metals from the rocks.

25

Why is strip mining harmful?

-health hazards for miners
-acid drainage which affects terrestrial and aquatic ecosystems

26

What is a turbine?

a rotating device that converts the kinetic energy of a moving substance, such as steam, into mechanical energy

27

What do clean coal technologies do?

focus on ridding the toxic chemicals of coal

28

when is natural "gas" a liquid?

at ambient pressures and temperature in subsurface reservoirs

29

what is technically recoverable oil?

oil that can be extracted with current technology

30

what are procen recoverable reserves

oil that is technologically and economically feasible to remove under current conditions