C2 2021

Question 1

Suggest why aqueous ethanol is a suitable solvent when heating the coconut oil with KOH

Answer 1

Allow dissolve both oil and KOH

Question 2

State the meaning of fraction as used in the term petrol fraction

Answer 2

Group of hydrocarbons that similar boiling points

Question 3

The student considered using a glass beaker on a tripod and gauze instead of the clamped copper calorimeter.
Suggest two disadvantages of using a glass beaker on a tripod and gauze

Answer 3

Glass poor conductor than copper
Tripod and gauze reduces heat transfer

Question 4

Explain in terms of structure and bonding why benzene is more thermodynamically stable than kekule

Answer 4

Electrons delocalised

Question 5

Suggest why chemists usually aim to design production methods with fewer steps
With a high percentage atom economy

Answer 5

Better yield
Less waste

Question 6

State how CFCs form chlorine atoms in upper atmosphere

Answer 6

C-Cl bonds broken

Question 7

Suggest why the order of this reaction with respect to propanone can be ignored in this experiment

Answer 7

Much larger than propanone
The concentration of propanaone constant