Practical 5 (Paper 2 +3) – Distillation of a product from a reaction.

Question 1

Anti-bumping granules

Answer 1

1a no anti-bumping granules / add anti-bumping granules
1b to create smaller bubbles / to prevent large bubbles / to
prevent mixture jumping into condenser

Question 2

Open system with no thermometer

Answer 2

2a system should be closed (above flask) to prevent gases escaping
2b should be closed with (bung +) thermometer
2c to allow collection of propanone (only) / to prevent
distillation of other components / to stay in suitable temperature
range

Question 3

the water direction in the condenser

Answer 3

3a In from the bottom out from the top / change water direction
3b condenser not cool enough / not full of water
3c product may not condense / comes through as gas//efficient cooling

Question 4

Ba2+

Question 5

SO42−

Answer 5

BaCl2
obs:white ppt
reason for obs:Formation of
BaSO4(s)
Ba2+(aq) + SO42−(aq)—> BaSO4(s)

Question 6

Mg2+

Answer 6

reasgent:NaOH
obs: white ppt
Formation of
Mg(OH)2(s)
equation:Mg2+(aq) + 2OH−(aq) à
Mg(OH)2(s)

Question 7

OH−

Answer 7

MgCl2
obs:White ppt.
obs for formation:Formation of Mg(OH)2(s)
eqaution:Mg2+(aq) + 2OH−(aq)—>
Mg(OH)2(s)

Question 8

Cl−

Answer 8

AgNO3
obs:White ppt.
reason for obs:AgCl(s)
equation:AgCl(s) Ag+(aq) + Cl−(aq) à AgCl(s)

Question 9

Br−

Answer 9

reagent:AgNO3
obs:Cream ppt.
reason for Formation :AgBr(s)
equation:Ag+(aq) + Br−(aq) à AgBr(s)