Alkenes and Alcohols Flashcards Preview

A Level chemistry year 1 > Alkenes and Alcohols > Flashcards

Flashcards in Alkenes and Alcohols Deck (24):
1

what is the general formula of an alkene?

CnH2n

2

why do alkenes react with electrophiles?

the double bond has lots of electrons so is easily attacked by electrophiles

3

what is an electrophile?

electron pair acceptor

4

what is a polymer?

long chain molecule formed when lots of small molecules (monomers) join together

5

what type of polymers do alkenes form?

addition polymers

6

why are polyalkenes with long straight chains stronger than those with short branched chains?

they can be packed more closely together so the VDW'd will be stronger

7

give two typical uses of rigid PVC

drainpipes and window frammes

8

what is the general formula for an alcohol?

CnH2n+2OH

9

what is the method of producing alcohols from alkenes?

hydration of alkenes gives an alcohol
hydrate an alkene using steam in the presence of an acid catylist

10

what is the method of producing alcohols from alkenes?

hydration of alkenes gives an alcohol
hydrate an alkene using steam in the presence of an acid catalyst

11

why should fermentation of glucose not be carried out at more than 40*c?

that is the enzymes optimal temp
too cold and its too slow
too hot and it is denatured

12

what is a biofuel?

a fuel that is made from biological material that's recently died

13

list two advantages of replacing fossil fuels with biofuels

biofuels are renewable so a more sustainable source of energy

its carbon neutral

14

list two disadvantages of replacing fossil fuels with
biofuels

petrol car engines would have to be modified to use fuels with high ethanol concentrations

there will be less land to grow food on as its used up for growing biofuels

15

how do you make ethanol from glucose?

fermentation of ethanol

16

what is the colour change when potassium dichromate(VI) is reduced?

the orange dichromate ion is reduced to the green chromium ion

17

describe the structure of an aldehyde

has a hydrogen and one alkyl group attached to carbon atom

functional group always on carbon-1
suffix is -al

18

describe the structure of a ketone

two alkyl groups attached to carbon atom
suffix is -one
if there is more than 5 carbons say which carbon the functional group is on

19

describe the structure of a carboxylic acid

has a COOH group at the end of the carbon chain
suffix is -oic acid

20

what will acidified potassium dichromate oxidise secondary alcohols to?

ketone

21

what are primary alcohols oxidised to?

aldehydes then carboxylic acids

22

what are secondary alcohols oxidised to?

ketones

23

what are tertiary alcohols oxidised to?

they aren't oxidised

24

describe two tests you can carry out to distinguish between an aldehyde and a ketone?

fehlings and benedicts solution are both deep blue and reduce to brick red when warmed with an aldehyde, but stay blue with a ketone

tollens reagent is reduced to form a silver mirror when warmed with an aldehyde, but not with a ketone