Natures Chemistry

Question 1

What is a hydrocarbon?

Answer 1

A compound containing hydrogen and carbon atoms only

Question 2

Describe the homologous series

Answer 2

Homologous series have similar chemical properties and the same general formula

Question 3

What is the general formula for Alkanes?

Answer 3

CnH2n+2

Question 4

General formula for Alkenes?

Answer 4

CnH2n

Question 5

General formula for Cyloalkanes?

Answer 5

CnH2n

Question 6

General formula for Alkanols?

Answer 6

CnH2n+1 OH

Question 7

General formula for Carboxyls?

Answer 7

CnH2n+1 COOH

Question 8

List the alkane family 1-8

Answer 8

1- Methane 
2- Ethane 
3- Propane 
4- Butane 
5- Pentane 
6- Hexane 
7- Heptane 
8- Octane

Question 9

List the alkene family 1-8

Answer 9

1- Methene
2- Ethene 
3- Propene 
4- Butene 
5- Pentene 
6- Hexene 
7- Heptene 
8- Octene

Question 10

list the Alkanol family 1-8

Answer 10

1- Methanol 
2- Ethanol 
3- Propanol 
4- Butanol 
5- Pentanol 
6- Hexanol 
7- Heptanol 
8- Octanol

Question 11

How to make an ester?

Answer 11

alcohol + Carboxylic acid = ester + water

Change the alochol to end in “yl” and the carboxylic acid ends in “oate”

Question 12

What is an Isomer?

Answer 12

Isomers have the same molecular formula but different structure. Such as Alkenes and cycloalkanes

Question 13

What is the general formula for the carboxyl group ?

Answer 13

CnH2n+1 COOH

Question 14

Name the carboxyl group?

Answer 14

1- Mehtanoic 
2- Ethanoic 
3- Propanoic 
4- Butanoic 
5- Pentanoic 
6- Hexanoic 
7- Heptanoic 
8- Octanoic

Question 15

What are uses for alcohols?

Answer 15

Solvents and fuels

Question 16

What are uses for Carboxylic acid?

Answer 16

Pickling, vinegar, soap and medicine

Question 17

What are uses for esters?

Answer 17

Perfumes and flavourings

Question 18

What does each symbol mean in:

E- Cm Delta T

What must you convert the “mass” into to work out answer?

Answer 18

E = energy 
C = Heat capacity of water (4.18) 
m= Mass in Kgs 
Delta = The difference between 
T= Temperature

Question 19

Above what boiling temperature is a liquid? and below what boiling point temperature is a gas?

Question 20

What is intermolecular bonding?

Answer 20

These are bonds created between molecules

Question 21

Why does butane have a higher melting point than methane?

Answer 21

Because butane has a higher melting point as there are more intermolecular forces to break - so requires more energy.

Question 22

What two properties increase, when the size of the molecule becomes smaller?

Answer 22

Boiling point and viscosity

Question 23

What two properties decease, when the size of the molecule is larger?

Answer 23

Ease of evaporation and flammability

Question 24

What does complete combustion of a hydrocarbon produce?

Answer 24

Complete combustion of a hydrocarbon provides carbon dioxide and water

Question 25

What is needed for complete combustion to take place?

Answer 25

a good oxygen supply

Question 26

What happens when there is not enough oxygen from the air and not all of the hydrocarbon are turned into carbon dioxide and water?

Answer 26

incomplete combustion happens when there is not enough oxygen in the air and not all the hydrocarbon will be turned into carbon dioxide and water

Question 27

What is crude oil?

Answer 27

Crude oil is a mixture of chemical compounds which can be separated by a process called fractional distillation

Question 28

Describe the term unsaturated?

Answer 28

Carbon to carbon bond

Question 29

Describe the term saturated?

Answer 29

single bond

Question 30

What happens when bromine is added to an unsaturated solution?

Answer 30

Bromine decolourises when added to an unsaturated solution