C3 Organic Chemistry

Question 0

If an alcohol has 2 carbon atoms, what is the formula?

Answer 0

C2 H5 OH

Question 1

What is the general formula for alcohols?

Answer 1

CnH2n+1OH.

There are twice the number of hydrogen atoms plus one and an extra OH.

Question 2

What is the functional group of alcohol?

Answer 2

-OH

Question 3

What is a homologous series?

Answer 3

A group of chemicals that react in a similar way because they have the same functional group. Like -OH

Question 4

Name the first three alcohols?

Answer 4

Methanol, Ethanol and Propanol.

Question 5

How are alcohols named?

Answer 5

Get rid of the E in the alkanes name and replace with an “ol”

Question 6

What do the first three alcohols have in common?

Answer 6

They are flammable,
dissolve completely in water to form neutral solutions.
react with sodium to give hydrogen and alkoxides.

Question 7

Give the equation for methanol burning in air.

Answer 7

2CH(small 3)OH + 3O(small) produce 2CO(small 2) + 4H(small 2)O
Carbon dioxide and water are produced.

Question 8

Give the equation of ethanol reacting with sodium.

Answer 8

2C”2”H”5”OH + 2Na produces 2C”2”H”5”ONa + H”2”

Question 9

How can alcohol be used as a solvent?

Answer 9

Methanol and ethanol can dissolve compounds that water can’t like hydrocarbons, oils and fats.
Ethanol is used in perfume and aftershave. It can mix with oils and the water.
Methylated spirit is ethanol with chemical added to it.
They can be used as fuel and can clean paint brushes.

Question 10

How can alcohol be used as a fuel?

Answer 10

Ethanol can be used as a fuel in spirt burners. Is burns clearly and it doesn’t smell.
Ethanol can be mixed with petrol to produce fuel for cars. It is cleaner than normal petrol.
Some nations with little oil but lots of land and sunshine can grow lots of sugar Caine to produce ethanol.
This is good as the sugar cane is renewable resource.

Question 11

What is the functional group of carboxylic acid?

Answer 11

-COOH

Question 12

How do you name a carboxylic acid?

Answer 12

It will start with meth,eth, or prop and end with anoic acid.

Question 13

What is the equation of methanoic acid ?

Answer 13

HCOOH

Question 14

What happens when you react carboxylic acid with metal?

Answer 14

They produce CO2 and a salt which will end with -anoate.

Methanoic acid will form methanoate and ethanoic acid will produce ethanoate.

Question 15

Give the word equation of ethanoic acid reacting with sodium carbonate

Answer 15

Ethanoic acid + sodium carbonate = carbon dioxide + sodium ethanoate.

Question 16

Why do carboxylic acids produce less acidic solutions when mixed with water?

Answer 16

When the acid dissolves in water, they ionise and release H+ ions which make the acid acidic. However they aren’t completely ionised so they form weak acidic solutions. This means they have a higher pH than aqueous solutions of strong acids with the same concentration.
For example
HCl forms H+ and Cl- ions.
CH”3”COOH forms H+ and CH”3”COO- ions. Only half of the hydrogens have been ionised.

Question 17

How can carboxylic acid be used in industry?

Answer 17

Long chained carboxylic acids with lots of carbon atoms are used is soaps and detergents.
They are used in the preparation of esters.
It is a good solvent for many organic molecules but it is seldom used as it makes the solution too acidic.

Question 18

Name some more common carboxylic acids and how they are formed.

Answer 18

Ethanoic acid is made by oxidising ethanol. Microbes cause the ethanol to ferment. It can also be used as an oxidising agent.
Ethanol + oxygen = ethanoic acid + water.
Ethanoic acid can be mixed with water to produce vinegar.
Citric acid can get with scale and is used in fizzy drinks.

Question 19

What is the functional group of esters?

Answer 19

-COO-

Question 20

How are esters formed?

Answer 20

An alcohol and a carboxylic acid are put together with an acid catalyst. (Sulphuric acid is normally used )
Alcohol + carboxylic acid = ester + water.

Question 21

How are the names of esters made and give an example

Answer 21

They names end in -oate.
The alcohol forms the first part if the esters name, and the acid forms the second part.
Ethanol + ethanoic acid = ethyl ethanoate + water.
Methanol + propanoic acid = methyl propanoate + water.

Question 22

What can esters be used for and not used for?

Answer 22

They smell nice, sweet and fruity. They are also volatile which means they make good perfumes.
However many are flammable meaning they are potentially dangerous.
Don’t mix well with water but do mix with alcohols and organic solvents.
Some are used as ointments.
Others are used as solvents for paint, ink, glue and nail varnish remover.

Question 23

What does have to be considered when using esters?

Answer 23

Inhaling the fumes from some of them irritates mucous membrane in the nose and mouth.
They are heavier than air and are very flammable. The can cause explosions.
In large doses some are toxic. Some people worry about the health problems.
However they aren’t as volatile or toxic as other organic solvents. They don’t produce as many toxic fumes and are replacing some solvents.

Question 24

What so all organic compounds have in common?

Answer 24

They all contain carbon.

Question 25

What is a homologous series?

Answer 25

A family of compounds with the same functional group.

Question 26

What is the general formula for alkanes?

Answer 26

CnH2n+2

Question 27

A alcohol is formed when one of the of an alkane is replaces by an

Answer 27

Hydrogens. -OH

Question 28

How do carboxylic acids form?

Answer 28

One of the carbons of the alkane will lose 3 of its hydrogen bonds and this will be replaced with a double bond with one oxygen and a bond will a OH.

Question 29

How do esters form from carboxylic acids?

Answer 29

The H in the -COOH group will be replaced with an hydrocarbon.

Question 30

How is ethanol made?

Answer 30

In industry Ethernet is added with steam.

In drinks sugars ferment.

Question 31

When alcohols burn in air, what do they form?

Answer 31

CO2 and water.

Question 32

What is the damage alcohol can do?

Answer 32

Liver damage, addiction, behaviour changes and DEATH.

Question 33

Why is alcohol expensive?

Answer 33

It has a tax. This is used for the NHS, policing drunkards and paying for days lost at work.

Question 34

What does Methylated spirit contain?

Answer 34

Toxic methanol, ethanol, emetics(makes you vomit), foul-tasting chemicals.

Question 35

Why are methylated spirits hard to distile?

Answer 35

Other substances with boiling points similar to ethanol are added.

Question 36

What are the advantages of biofuel?

Answer 36

Almost carbon neutral.

Re-new able resource.

Question 37

What are the disadvantages of biofuel?

Answer 37

Takes up a lot of land.
Food prices go up.
De-forestation.

Question 38

What happens when alcohol is reacted with a group one metal?

Answer 38

It will be the same as water, but less rigours. Fizzing and Hydrogen would be made.

Question 39

What happens when alcohol is oxidised?

Answer 39

It will form a carboxylic acid.

Question 40

What happens when alcohol is left in air?

Answer 40

It will oxidise in the air, producing carboxylic acid.

Question 41

How ells, other than leaving it in air, can alcohol be oxidised?

Answer 41

Add an oxidising agent. (Potassium dichromate)