Give reasons for the following.
(a) Aluminium
foils are used to wrap food items.
(b) Immersion
rods for heating liquids are made up of metallic substances.
(c) Copper
cannot displace zinc from its salt solution.
(d) Sodium
and potassium are stored in kerosene.
Give reasons for the following.
(a) Aluminium foils are used to wrap food items.
(b) Immersion rods for heating liquids are made up of metallic substances.
(c) Copper cannot displace zinc from its salt solution.
(d) Sodium and potassium are stored in kerosene.
(a) Aluminium foils are
used to wrap food items because aluminium metal is malleable.
Therefore, it can be beaten into thin foils.
(b) Metals are good
conductors of heat and electricity. Therefore, immersion rods for
heating liquids are made of metallic substances.
(c) A metal can displace
a less reactive metal from its salt in an aqueous solution. But zinc
is more reactive than copper. Therefore, copper cannot displace zinc
from its salt solution.
Cu(s)
+ ZnSO4 (aq)
→
No reaction
(d) Sodium
and potassium are stored in kerosene because they are highly
reactive elements. They can easily catch fire even when in contact
with air.
(a) Aluminium foils are used to wrap food items because aluminium metal is malleable. Therefore, it can be beaten into thin foils.
(b) Metals are good conductors of heat and electricity. Therefore, immersion rods for heating liquids are made of metallic substances.
(c) A metal can displace a less reactive metal from its salt in an aqueous solution. But zinc is more reactive than copper. Therefore, copper cannot displace zinc from its salt solution.
Cu(s) + ZnSO4 (aq) → No reaction
(d) Sodium and potassium are stored in kerosene because they are highly reactive elements. They can easily catch fire even when in contact with air.
