Chapter 1 - Choosing Fuels Flashcards Preview

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Flashcards in Chapter 1 - Choosing Fuels Deck (30):
1

What is a fuel?

A substance used to produce energy or power, usually by combustion

2

What is a renewable energy?

A source or fuel that can be replenished by natural means and can be manufactured faster than they are used by society.

3

Examples of renewable energy

Solar, Wind, Hydro

Biofuels

4

What is a non-renewable energy?

A source or fuel that cannot be replenished faster than they are used by society.

5

examples of non-renewable energy

Coal, Petroleum, Natural Gas

6

How is bioethanol created?

By the fermentation of sugars found in plant and animal waste. These sugars include Molasses and Starch.

7

Pros/Cons of Bioethanol

-less pollutant emission as it is made from natural waste
-renewable

-less energy is released relative to petrol and it is quite expensive

8

How is biodiesel created?

Fatty acids in products such as vegetable oils, animal fats and cooking oil undergo transesterification to produce biodiesel

9

Pros/Cons of Biodiesel

-Biodegradable less pollutant emissions like SO2
-renewable

-High viscosity may cause it to 'gel' in cold climates thus not suitable
-crops take up space which could be used for food crops

10

How is Biogas created?

Biogas is a mixture of gases, mainly methane, that are produced by the anaerobic fermentation of animal and plant waste.

11

Pros/Cons of biogas

-Can be produced on a large scale
-can generate many types of energy

-low energy released
-no cons

12

What is kinetic energy?

Energy associated with movement, in doing work.

13

What is potential energy?

Energy that is stored, ready to do work.

14

What is energy?

Energy is defined as the ability to do work. It is measured in the unit "joules".

15

What is a thermochemical equation?

A chemical equation that also shows the quantity of heat energy given out or absorbed when a mole of a substance is burned.

16

What is the Law of Conservation of Energy?

Energy is neither created or destroyed but transferred into other forms

17

What affect does many transfers of energy have?

Although quantity of energy can stay the same the quality becomes worse. Some energy is lost as heat etc.

18

What is energy efficiency?

How efficient a substance is refers to how much of it can actually be transferred into a new form of energy.

19

Energy Efficiency formula

(energy obtained/energy that was available) x 100

20

Pros/Cons of oil

-wide range of uses

-non-renewable
-pollution

21

Pros/Cons of coal

-easily mined
-source of revenue for AUS

--global warming
-non-renewable

22

Pros/Cons of Natural gas

-high efficiency
-moderate cost

-non-renewable
-pollution

23

What fuel has the highest heat content per gram?

Natural Gas/Methane

24

What is the enhanced greenhouse effect

"Enhanced" refers to pollutant emissions having an affect on the world and affecting global warming, the ozone layer etc.

"Not enhanced" refers to water being the largest contribution in the form of clouds reflecting sunlight onto the ozone layer.

25

PD AND BD

Intermolecular bonding

PD
Dispersion forces (non-polar)

BD
Dispersion and dipole (ester group)

26

PD AND BD

Viscosity

BD
Has a higher viscosity than PD and therefore may tend to 'gel' in cold climates and be rendered useless.

27

PD AND BD

Cloud Point

Cloud Point is the lowest temperature at which crystals start to form

BD
Has a higher cloud point which makes it unsuitable for cold climates.

28

PD AND BD

Hydroscopic

PD
Slightly

BD
More hydroscopic than PD which leads to lower fuel efficiency.

29

PD AND BD

Energy Content

PD
Has a higher energy density than bio diesel.

30

PD AND BD

Source

PD
Crude oil --> fractional distillation

BD
Transesterification from triglycerides +ethanol/methanol
85 deg C