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Flashcards in ALKANES Deck (29)
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1

Definition: Aliphatic

Containing Carbon atoms joined together in straight or branched chains

2

Definition: Alicyclic

Containing Carbon atoms joined together in a ring that is not aromatic

3

Definition: Aromatic

Containing one or more benzene rings

4

Definition: Saturated

Containing only single bonds

5

Definition: Unsaturated

Containing a multiple carbon-carbon bond

6

Definition: Homologous group

A series of organic compounds having the same functional group but with each successive member differing by CH2

7

Definition: A functional group

A group of atoms responsible for the characteristic reactions of a compound

8

General formula for alkanes

Cn H2n+2

9

General formula for cycloalkanes

Cn H2n

10

General formula for alkynes

Cn H2n-2

11

Definition: Empirical formula

The simplest whole number ratio of atoms of each element present in a compound

12

Definition: Skeletal formula

A simplified organic formula, with the hydrogen atoms removed from alkyl chains, leaving just a carbon skeleton and associated functional groups

13

Definition: General formula

The simplest algebraic formula of a member of a homologous series

14

Definition: Molecular formula

The actual number of atoms of each element in a molecule

15

Definition: Structural formula

The minimal detail that shows the arrangement of atoms in a molecule

16

Definition: Displayed formula

The relative positioning of all the atoms in a molecule including the bonds between them

17

Functional group of aldehyde

CHO

18

Functional group of ketone

C(CO)C

19

Functional group of carboxylic acid

COOH

20

Definition: Structural isomers

Molecules with the same molecular formula but different structure

21

List the 3 ways structural isomers can occur

-Chain isomers: The hydrocarbon chain may be branched or unbranched
-Position isomers: The hydrocarbon chain stays the same but the functional group is found in different positions along the chain
-Functional group isomers: The functional group is different eg. Alkenes and cycloalkanes

22

What is the effect of branching on boiling point?

More branching means a lower boiling point because the contact area between molecules is smaller and therefore the London forces are weaker and therefore less energy is required to overcome them.

23

Why are alkanes relatively unreactive?

Alkanes only contain C-C and C-H bonds which are very strong and therefore hard to break. The are also non-polar so they can attract other species either.

24

General formula for the complete combustion of a hydrocarbon of formula CxHy

CxHy + (x + 1/4y)O2 -> xCO2 + 1/2yH2O

25

What condition is needed for an alkane to react with a halogen and what type of reaction is this?

UV light + substitution reaction

26

Definition: Radical

A radical is a species with a single unpaired electron

27

Name the 3 stages of free radical substitution

Initiation, Propagation, Termination

28

Definition: Homolytic fission

The breaking of a covalent bond with one of the bonded electrons going to each atom, forming two radicals

29

Three limitations of using radical substitution in organic synthesis

1. Further substitution can occur
2. Substitution at different points in the C chain can happen
3. The C chain might double in length