2.1 Hydrocarbons Flashcards Preview

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Flashcards in 2.1 Hydrocarbons Deck (34)
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1

What is a "hydrocarbon"?

A compound containing only C and H atoms

2

What is a Homologous Series?

Molecules with

 

  • same general formula
  • similar chemical properties
  • gradation in physical properties

3

What are the names of the alkanes from 1C to 8C atoms in molecules?

4

What is meant by a saturated hydrocarbon?

A hydrocarbon where all C-C bonds present are single

5

What is the 3D shape of methane (CH4) ?

Tetrahedral

6

What is shown by a "Molecular Formula" ?

The types of atom and their relative abundance in a molecule. The abundance is shown as subscript

e.g

H2O

C3H8

NH3

CO2

7

What is shown in a "Full Structural Formula"?

All the atoms and all the covalent bonds connecting them in a molecule

 

8

What is shown in a shortened structural formula?

Each C in the chain is shown with everything bonded to it (not other C atoms in chain) No bonds need to be shown , although C=C bonds are allowed

9

What is the general formula of the alkanes?

10

What are the 2 main reactions of alkanes?

1. Combustion

2. Catalytic cracking

11

Why is catalytic cracking an important reactions for longer chain alkanes?

  1. To produce shorter chain, more useful alkanes
  2.  To obtain alkenes which are useful reactants to make other products

12

What are the products of complete alkane combustion?

CO2 and H2O

13

How do we test for the products of combustion of a hydrocarbon?

14

What are possible harmful products of incomplete combustion of hydrocarbons?

15

What is meant by the term "isomers"?

Compounds with the same molecular formula but different structural formula. 

16

Why does the boiling point of the alkanes increase as you add C (and H) atoms?

The larger molecules have stronger attractions between them that require more energy to be broken

17

What is meant by an unsaturated hydrocarbon?

A hydrocarbon with (at least) one C=C bonds present 

18

What is a "hydrocarbon"?

A compound containing only C and H atoms

19

What is a Homologous Series?

Molecules with

 

  • same general formula
  • similar chemical properties
  • gradation in physical properties

20

What is the general formula of the alkenes?

Cn H2n

21

What are isomers?

Compounds with the same molecular formula but different structural formulae

22

How are alkenes produced?

Catalytic cracking of longer chain alkanes

24

What is meant by a "functional group"?

The part of a molecule that is responsible for the chemical (and sometimes physical) properties of the compound.

25

What is the functional group of the alkene family?

C=C bond

26

What reactions do alkenes undergo?

Addition reactions

27

What specific name to we give to to the addition a halogen to an alkene?

Halogenation

28

What specific name to we give to to the addition of hydrogen to an alkene?

Hydrogenation

29

What is produced when an alkene undergoes a hydrogenation reaction?

An alkane

30

What is produced when an alkene undergoes a hydration reaction?

An alcohol

31

What is the chemical test for presence of unsaturation (C=C bond)

Rapidly decolourises bromine solution.

32

What specific name to we give to to the addition of water to an alkene?

Hydration

33

What is the general formula for the cycloalkanes?

Cn H2n

34

Are cycloalkanes saturated or unsaturated?

They are saturated molecules.

35

What are some uses of cycloalkanes?

  • Fuels
  • solvents