Topic 5 - Homologous series

Question 1

What is a homologous series

Answer 1

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

Question 2

What is often seen in the physical properties of the members of a homologous series?

Answer 2

patterns

Question 3

What happens to the melting and boiling points as you move along a homologous series?

Answer 3

the melting and boiling points generally increase as the molecular size increases

Question 4

Why do melting and boiling points increase as the molecular size increases in a homologous series?

Answer 4

due to the increasing strength of the intermolecular forces as the molecular size increases

Question 5

What are hydrocarbons?

Answer 5

compounds containing only hydrogen and carbon atoms

Question 6

What is a saturated compound?

Answer 6

a compound that contains only single carbon–carbon bonds

Question 7

What is an unsaturated compound?

Answer 7

a compound that contains at least one carbon–carbon double bond

Question 8

How to test for unsaturated compounds?

Answer 8

using bromine water. Unsaturated compounds decolourise bromine solution quickly

Question 9

What are isomers?

Answer 9

compounds with the same molecular formula but different structural formulae

Question 10

What are the differences between isomers

Answer 10

they may belong to different homologous series
they usually have different physical properties

Question 11

Given a structural formula for a compound, an isomer can be drawn.
Isomers can be drawn for a given molecular formula.

Answer 11

LEARN this

Question 12

What are alkanes?

Answer 12

a homologous series of saturated hydrocarbons

Question 13

What are alkanes commonly used as?

Answer 13

fuels

Question 14

Are alkanes soluble in water?

Answer 14

no

Question 15

What is the alkanes general formula

Answer 15

CₙH₂ₙ₊₂

Question 16

What can you do from the structural formlua of an alkane (if it has 8 or less carbons)?

Answer 16

you can name it

Question 17

What can you do from the name of an alkane (if it has 8 or less carbons)?

Answer 17

you can write the molecular formula and draw the structural formula

Question 18

What are cycloalkanes?

Answer 18

a homologous series of saturated, cyclic hydrocarbons

Question 19

What are cycloalkanes commonly used as?

Answer 19

fuels and solvents

Question 20

Are cycloalkanes soluble in water?

Answer 20

no

Question 21

What is the cycloalkane general formula

Answer 21

CₙH₂ₙ

Question 22

How can cycloalkanes be named?

Answer 22

from their structural formulae

Question 23

What can you do from the name of an unbranched cycloalkane?

Answer 23

You can write the molecular formula and draw the structural formula

Question 24

What are alkenes?

Answer 24

a homologous series of unsaturated hydrocarbons

Question 25

What are alkenes commonly used to make?

Answer 25

polymers and alcohols

Question 26

Are alkenes soluble in water

Answer 26

no

Question 27

What functional group do alkenes contain?

Answer 27

the C=C double bond

Question 28

What is the general formula for the alkenes

Answer 28

CₙH₂ₙ

Question 29

What can you know from an alkenes structural formula (with up to 8 carbons)?

Answer 29

you can name it, showing where the double bond is

Question 30

What can you know from the name of an alkene (with up to 8 carbons)?

Answer 30

you can write its molecular formula, and draw its structural formula

Question 31

What type of reactions do alkenes undergo?

Answer 31

addition reactions

Question 32

What do alkenes undergo addition reactions with?

Answer 32

hydrogen, halogens and water

Question 33

What is formed when an alkene reacts with hydrogen?

Answer 33

an alkane, this reaction is called hydrogenation

Question 34

What is formed when an alkene reacts with a halogen?

Answer 34

a dihaloalkane is formed

Question 35

What is formed when an alkene reacts with water?

Answer 35

an alcohol, this reaction is called hydration