Organic

Question 1

What is crude oil?

Answer 1

Non-renewable fuel, made of hydrocarbons of different lengths

Question 2

Describe the characteristics of alkanes.

Answer 2

Single carbon bond, saturated.

Question 3

Why are alkanes saturated?

Answer 3

Because no more hydrogen atoms can be added to them.

Question 4

What is the general formula of alkanes?

Answer 4

CnH2n+2

Question 5

Describe the characteristics of alkenes.

Answer 5

Double bond, unsaturated.

Question 6

Why are alkenes unsaturated?

Answer 6

More atoms can be added to the carbon atoms that are double bonded.

Question 7

What is the general formula of alkenes?

Answer 7

CnH2n

Question 8

What is the word formula for the combustion of alkenes?

Answer 8

Alkene + oxygen → carbon dioxide + water

Question 9

What is the word equation for the hydrogenation of an alkene?

Answer 9

Alkene + hydrogen → alkane

Question 10

What is hydrogenation?

Answer 10

Addition of hydrogen.

Question 11

What reactions can alkenes undergo?

Answer 11

Combustion, hydrogenation, adding halogens.

Question 12

What does a structural formula show?

Answer 12

The arrangement of atoms carbon by carbon, with hydrogens and functional groups attached after each one.

Question 13

What is a hydrocarbon isomer?

Answer 13

A hydrocarbon with the same molecular formula but a different displayed and structural formula.

Question 14

What types of reactions occur with organic compounds and hydrocarbons?

Answer 14

Substitution (alkanes only) and addition (alkenes only).

Question 15

What is substitution of hydrocarbons?

Answer 15

Only involves alkanes. One functional group is replaced by another.

E.g. CH₄ + Cl₂ → CH₃Cl + HCl

Question 16

What is addition of hydrocarbons?

Answer 16

Alkenes only. Two or more molecules join together to form a larger molecule.

E.g. ethene + steam → ethanol

Question 17

What is fractional distillation?

Answer 17

Splitting hydrocarbon chains into groups based on their length

Question 18

What happens to hydrocarbons as they get longer?

Answer 18

Its melting point increases, becomes less flammable, becomes darker, becomes more viscous.

Question 19

What is crude oil?

Answer 19

A mixture of different hydrocarbons.

Question 20

What is the order of hydrocarbon fractions by chain length?

Answer 20

Refinery gases, gasoline, kerosene, diesel, fuel oil, bitumen.

Question 21

What is the use of refinery gases?

Answer 21

Bottled gas.

Question 22

What is the use of gasoline?

Answer 22

Fuel for cars.

Question 23

What is the use of kerosene?

Answer 23

Fuel for planes.

Question 24

What is the use of diesel?

Answer 24

Fuel for lorries.

Question 25

What is the use of fuel oil?

Answer 25

Fuel for boats/ships.

Question 26

What is the use of bitumen?

Answer 26

Road surfacing.

Question 27

Explain how fractional distillation works.

Answer 27

Crude oil is separated by fractional distillation. Crude oil is heated to 350°C and evaporates. The gas enters a fractional distillation column and the temperature decreases as it rises. Fractions with higher boiling points condense and are collected nearer the bottom. Shorter chains rise higher before condensing.

Question 28

What is the word formula for incomplete combustion of alkanes?

Answer 28

Alkane + oxygen → carbon monoxide + water

Question 29

Why is carbon monoxide dangerous?

Answer 29

Haemoglobin in red blood cells binds more readily to carbon monoxide than oxygen, reducing the blood’s oxygen-carrying capacity.

Question 30

What does the reaction between alkenes and halogens form?

Answer 30

Dihaloalkanes.

Question 31

What happens during the reaction between alkenes and halogens?

Answer 31

The double bond breaks, allowing a halogen diatomic molecule to bond across the two carbon atoms.

Question 32

How can you test for the presence of alkenes?

Answer 32

Add to bromine water. If a double bond is present, the solution turns from orange to colourless. If not, it stays orange.

Question 33

What is the functional group of alcohols?

Answer 33

OH

Question 34

Which methods are used to oxidise ethanol?

Answer 34

Complete combustion, microbial oxidation (reaction with oxygen in the air to form ethanoic acid), heating with potassium dichromate in dilute sulfuric acid to form ethanoic acid.

Question 35

How can you manufacture ethanol?

Answer 35

React ethene with steam using a phosphoric acid catalyst at 300°C, ferment glucose anaerobically at 30°C.

Question 36

What is the functional group of carboxylic acids?

Answer 36

COOH

Question 37

How do carboxylic acids behave in reactions?

Answer 37

Similarly to normal acids, but slightly slower. They still react with metals and carbonates.

Question 38

Which carboxylic acid does vinegar contain?

Answer 38

Ethanoic acid.

Question 39

What is the functional group of esters?

Answer 39

COO

Question 40

Give an example of a reaction that produces the ester ethyl ethanoate

Answer 40

Ethanoic acid + ethanol ⇌ ethyl ethanoate + water

Question 41

What is the structural formula of ethyl ethanoate?

Answer 41

CH₃COOCH₂CH₃

Question 42

What catalyst is required to form esters?

Answer 42

Sulfuric acid (usually).

Question 43

Why is water produced in ester formation?

Answer 43

The OH group from the acid and an H from the alcohol form H₂O, leaving behind the COO group in the ester.

Question 44

What does volatile mean?

Answer 44

Something that evaporates easily.

Question 45

What are esters used for?

Answer 45

Food flavourings and perfumes.

Question 46

Describe the experiment to produce ethyl ethanoate.

Answer 46

Mix equal volumes of carboxylic acid and alcohol in a flask. Add a catalyst of sulfuric acid. Submerge flask in a hot water bath and heat to a simmer. Collect ester from the flask.

Question 47

How are addition polymers created?

Answer 47

By joining together many monomers in a chain.