Chem

Question 1

When a substance combusts, it reacts with …

Answer 1

Oxygen

Question 2

C + O2 –> …

Answer 2

CO2

Question 3

Write a balanced equation for the combustion of carbon.

Answer 3

C + O2 –> CO2

Question 4

Write a balanced equation for the combustion of hydrogen.

Answer 4

H2 + 1/2 O2 –> H2O

Question 5

What does a hydrocarbon produce when it combusts ?

Answer 5

Carbon dioxide + water

Question 6

Crude oil is…

Answer 6

A mixture of many different hydrocarbons

Question 7

What can the trend of melting and boiling points of the Fractions be explained by ?

Answer 7

Intermolecular forces

Question 8

What does fractional distillation produce ?

Answer 8

Long chain hydrocarbons

Question 9

What industrial method is used to produce a mixture of smaller molecules after fractional distillation ?

Answer 9

Cracking

Question 10

Aluminium oxide
C18H38 —-> C10H22 + ……….
Catalyst

Answer 10

C8H16

Question 11

In cracking, what allows the reaction to take place at a lower temp ?

Answer 11

A catalyst

Question 12

A homologous series is …

Answer 12

A family of compounds with the same general formula and similar chemical properties

Question 13

Name this alkane

     H. H. H. H
      I.  I.   I.  I
H-C-C-C-C-H
      I   I.   I.  I
     H. H. H. H

Answer 13

Butane

Question 14

Name this alkane 
                          H
                           I
                    H- C- H
            H    H     I   H
             I      I      I      I
        H-C - C - C - C-H
              I.     I.    I.    I 
             H.    H.  H.  H

Answer 14

2 methyl butane

C5H12

Question 15

What is the formula mass of pentane ?

Answer 15

C5H12
= (12 x 5) + (1x12)
= 60 + 12
= 72 AMU

Question 16

Write a balanced equation for the combustion of hexane

Answer 16

C6H14 + 9.5 O2 –> 6 CO2 + 7 H2O

Question 17

Draw Propene

Answer 17

H. H. H. 
      I.  I.   I.  
H-C-C=C
      I        I.  
     H.     H.

Question 18

What is the general formula for the cycloalkanes ?

Answer 18

CnH2n

Question 19

What is the general formula for the cycloalkenes ?

Answer 19

CnH2n-2

Question 20

What is the general formula for the alkanes ?

Answer 20

CnH2n+2

Question 21

What is the general formula for the alkenes?

Answer 21

CnH2n

Question 22

What are isomers ?

Answer 22

Compounds with the same molecular formula but different structural formula

Question 23

Cycloalkanes and alkenes with the same number of carbons are….

Answer 23

Isomers

Question 24

Are alkanes saturated ?

Answer 24

Yes

Question 25

Are alkenes saturated ?

Answer 25

No

Question 26

What happens to bromine solution when an alkene is added

Answer 26

It decolourises

Question 27

What happens when an alkene reacts with hydrogen

Answer 27

An alkane is formed

Question 28

What is another name for alcohols

Answer 28

Alkanols

Question 29

Are alcohols soluble/insoluble in water ?

Answer 29

Soluble

Question 30

How could you distinguish an alcohol from another substance

Answer 30

It's highly flammable and burn with a clean flame

Question 31

What do alcohols react with to produce an ester ?

Answer 31

Carboxylate acids

Question 32

What group does an alcohol have ?

Answer 32

Hydroxyl (-OH)

Question 33

Name the alcohol with seven carbon atoms

Answer 33

Heptanol

Question 34

What do carboxylate acids have in common

Answer 34

Graded physical properties such as me,ting and boiling points

Question 35

What's the functional group in a carboxylic acid ?

Answer 35

Carboxyl (-COOH)

Question 36

What's the ending of carboxylic acids

Answer 36

Oic

Question 37

Name a carboxylic acid with 5 carbon atoms

Answer 37

Pentanoic acid

Question 38

What is the chemical name for vinegar

Answer 38

Ethanoic acid

Question 39

What is vinegar used for

Answer 39

Cleaner Food preservative Food flavouring

Question 40

pH level of carboxylic acid

Answer 40

<7

Question 41

What is the ester group

Answer 41

COO

Question 42

How are esters formed

Answer 42

By a reaction between an alcohol and a carboxylic acid

Question 43

Uses of esters

Answer 43

Food flavouring Industrial solvents Fragrances Materials

Question 44

How is the ester link formed

Answer 44

By the reaction of a carboxyl group and a hydroxyl group

Question 45

What type of reaction is the burning of fuel

Answer 45

Exothermic

Question 46

What does a substance react with when it burns

Answer 46

Oxygen

Question 47

Give another word for burning

Answer 47

Combustion

Question 48

What's the energy change in an exothermic reaction

Answer 48

Chemical--> heat

Question 49

What's the energy change in an endothermic reaction

Answer 49

Heat--> chemical

Question 50

What equation is uses to calculate the quantity of heat energy produced from a reaction

Answer 50

E = m X c X 🔼t

Question 51

How can u distinguish a carboxylic acid from another substance

Answer 51

pH <7

Question 52

How do you distinguish an alkene from another substance

Answer 52

It decolourises bromine solution