Chem test april 23.

Question 1

What is an exothermic reaction?

Answer 1

A reaction where energy is released.

Question 2

What is a fuel?

Answer 2

A fuel is a chemical that is burned to release energy.

Question 3

What is needed to make a fire reaction?

Answer 3

It requires heat, oxygen, fuel.

Question 4

What are the three fossil fuels?

Answer 4

Coal, natural gas and, crude oil. (also peat is a fossil product that becomes coal over time)

Question 5

How are coal and peat formed?

Answer 5

Coal and peat is made from plants millions and millions of years old that have been burried under layers and layers of rock and dirt, pressure and heat resulted in the substance being formed, though peat is the precursor to coal, The thing that comes before it.

Question 6

How is natural gas and oil formed?

Answer 6

These are products of organic matter, mostly tiny marine organisms, that has been decomposed over the past 550 million years.

Question 7

Why are fossil fuels called fossil fuels?

Answer 7

They are formed from decomposed matter from millions of years ago whicj is why they are “fossil” fuels.

Question 8

Are fossil fuels renewable?

Answer 8

No becuase they will eventually run out.

Question 9

What shape is a methane molecule?

Answer 9

Tetralhedral (like a pyramid).

Question 10

What are the alkanes?

Answer 10

Alkanes are a group of hydrocarnbons that are organic compounds made from carbon and hydrogen only with only single bonds.

Question 11

What are the first ten alkanes in order?

Answer 11

• Methane
• Ethane
• Propane
• Butane
• Pentane
• Hexane
• Heptane
• Octane
• Nonane
• Decane

Question 12

If a compound ends in ane it means?

Answer 12

That the carbon to carbon bonds are singular.

Question 13

If a compound ends in ene it means?

Answer 13

That the carbon to carbon bonds are double bonds.

Question 14

What is the molecular formula for methane?

Answer 14

CH4

Question 15

What is the molecular formula for ethane?

Answer 15

C2H6

Question 16

What is the molecular formula for propane?

Answer 16

C3H8

Question 17

What is the molecular formula for butane?

Answer 17

C4H10

Question 18

What is the molecular formula for pentane?

Answer 18

C5H12

Question 19

What is the molecular formula for hexane?

Answer 19

C6H14

Question 20

What is the molecular formula for heptane?

Answer 20

C7H16

Question 21

What is the molecular formula for Octane?

Answer 21

C8H18

Question 22

What is crude oil?

Answer 22

Crude oil is a mixture of hydro carbons with different carbon chain lengths.

Question 23

What is a carbon chain length?

Answer 23

The number of carbon joined together in a chain.

Question 24

What is a hydrocarbon?

Answer 24

A compound of hydrogens and carbons.

Question 25

How is crude oil seperated?

Answer 25

Crude oil is separated into fractions using fractional distillation.

Question 26

How does factional distilation work?

Answer 26

Heated crude oil enters a fractional column which is hot at the bottom and gets cooler and cooler going up the column vapours from the crude oil rise up through the column and condense when at the right temperature, each fraction is then led to a different tube. The crude oil is now seperated into fractions.

Question 27

What are biofuels?

Answer 27

A biofuel is a natural and renewable fuel source.

Question 28

How is biomass produced?

Answer 28

The renewable organic material that comes from plants and animals that contains carbohydrates.

Question 29

What are 5 examples of biomass?

Answer 29

* Manure * Sugar cane * wood pelets * Logs * Food waste

Question 30

How can biofuel be considered carbon neautral?

Answer 30

The carbon dioxide that is released when using biofuel is the same amount captured from photosynthesis.

Question 31

How can lime water be used to test for carbon dioxide?

Answer 31

The lime water turns cloudy when carbon dioxide is detected.

Question 32

If ol is at the end of a compound it tells us?

Answer 32

It indicates alcohol.

Question 33

What are the products of combustion when burning a hydro carbon?

Answer 33

Water and carbon dioxide.

Question 34

Use a word equation to describe the combustion of a hydrocarbon?

Answer 34

Hydrocarbon + oxygen -> carbon dioxide + water.

Question 35

What is the chemical test for water?

Answer 35

Cobalt chloride paper turning pink.

Question 36

What is fermentation?

Answer 36

Fermentation is the proccess of a substance breaking down into a simpler substance. Organic molecules are converted into acids, gases, or alcohol.

Question 37

What is a word equation for the fermentation of glucose into ethanol?

Answer 37

Glucose -> ethanol + carbon dioxide.

Question 38

Name three substances that come from crude oil through fractional distilation and what are they used for?

Answer 38

.Petrol, petrol is a fuel used in vehicles and and produce electricity .Diesel, deisel is a fuel used in vehicles and machinery .Gas, gas is used for cooking and heating