Alcohols

Question 1

Alcohol general formula

Answer 1

Cn H2n+1 OH

Question 2

How to say CH3OH

Answer 2

Methanol

Question 3

How to say CH3CH2CH(OH)CH3

Answer 3

Butan-2-ol

Question 4

How to name alcohols

Answer 4

Ends with ol
Count from OH
OH number goes in middle after n before ol

Question 5

Aldehyde general formula

Answer 5

R-CHO

Question 6

How to name aldehyde

Answer 6

Ends in al (anal)
Number of OH not said, number of other functional groups is as normal
=O and H always at end of aldehyde

Question 7

Name CH3CH2CHO

Answer 7

Propanal

Question 8

Name CH2(CH3)CH(CH3)COH

Answer 8

2-methylbutanal

Question 9

Ketone general formula

Answer 9

R-CO-R
=O is not at end, can be anywhere

Question 10

How to name ketones

Answer 10

End with one
Number goes in middle

Question 11

Name CH3COCH3

Answer 11

Propanone

Question 12

Name CH3CH2CH2CHOCH3

Answer 12

Pentan-2-one

Question 13

General formula of carboxylic acids

Answer 13

R-COOH

Question 14

How to name carboxylic acids

Answer 14

Ends in oic acid
Number of functional groups go at start
=O and OH go at end so don’t say number in middle

Question 15

Name CH3CH(CH3)COOH

Answer 15

2-methylpropanoic acid

Question 16

Name HCOOH

Answer 16

Methanoic acid

Question 17

Alkenes test

Answer 17

1) 1cm3 Br water + 2 drops alkene
2) Shake vigorously
3) Orange -> colourless

Question 18

Carboxylic acid test

Answer 18

1) Sodium carbonate
2) Test gas with limewater
3) Turn cloudy with CO2 (if present) and white ppt

Question 19

Halogenoalkane test

Answer 19

1)Heat (60C) sodium hydroxide and ethanol
2) Acidify with nitric acid + silver nitrate
3) Chloride -> white
Bromide -> cream
Iodide -> yellow

Question 20

Aldehyde

Answer 20

1) Heat Fehlings, blue solution and red ppt
2) Heat Tollen’s reagent, silver mirror forms

Question 21

Alcohol

Answer 21

1) Heat with K2Cr2O7 + H2SO4
2) orange -> green (pri or secon) no change in tert

Question 22

Stage 1 of purifying the product of a reaction (practical 5)

Answer 22

1) Add concentrated H2SO4 and H3PO4 to flask containing cyclohexanol
2) swirl and add 3 drops carborundum
3) Connect flask to distillation apparatus
4) Heat at 83C so evaporates into condenser
5) Condenser has cold water so gases turn to liquids again
6) Liquids collected in cooled flask

Question 23

Stage 2 purifying the product of a reaction

Answer 23

1) Transfer product to separating funnel and add water for purifying
2) Mixture separate into layers, drain layer at bottom so cyclohexene remains

Question 24

Stage 3 purifying the product of a reaction

Answer 24

1) Drain off impure cyclohexene into round-bottomed flask
2) Add anhydrous CaCl2 removing water and stopped flask
3) Let mixture dry 20 mins
4) Distil again and only collect product distilled whebn mixture at 83C

Question 25

What do primary alcohols form

Answer 25

Aldehydes and carboxylic acids

Question 26

How do primary alcohols form aldehydes and carboxylic acids

Answer 26

Heat with K2Cr2O7 + H2SO4 and distill off product

Question 27

What do aldehydes form

Answer 27

Carboxylic acids

Question 28

How do aldehydes form carboxylic acids

Answer 28

Heat with Tollens reagent or Fehlings solution

Question 29

What do secondary alcohols form

Answer 29

Ketones

Question 30

2 ways of making alcohols

Answer 30

Hydration using steam
Fermentation using glucose

Question 31

Conditions of fermentation of glucose to form alcohols

Answer 31

Yeast
No oxygen
37C

Question 32

Advantages of biofuels

Answer 32

1) Renewable energy sources so is sustainable
2) Carbon neutral

Question 33

Disadvantages of biofuels

Answer 33

1) Can use land to grow crops for food not fuel
2) Sometimes have to deforest to get land to grow crops
3) Fertilisers added to soil to increase production, can be polluting waterways and release nitrous gases