Q.3. What happens when (write balanced equation in each case)
a) Hydrated ferrous sulphate crystals are strongly heated.
b)Lead nitrate is strongly heated.
c)Potassium chlorate is strongly heated.
d)Water is added over magnesium nitride.
e) Steam is passed over heated iron.
f) Hydrated copper sulphate crystals are strongly heated.
g) Gold particles are put in hydrochloric acid.
Answers
The following reactions happen for the following:
(a) On heating, first FeSO4 loses water to form anhydrous ferrous sulphate.
FeSO4.xH2O + Heat → FeSO4 + xH2O
- Upon strong heating, anhydrous FeSO4 gets decomposed and Fe2O3, SO2 and SO3 are formed.
2 FeSO4 + Heat → Fe2O3 + SO2 + SO3
(b) When lead nitrate is strongly heated, lead oxide, nitrogen dioxide and oxygen are obtained.
2 Pb(NO3)2 + Heat → 2 PbO + 4 NO2 + O2
(c) Potassium chlorate on strong heating decomposes to the potassium chloride and oxygen gas.
2 KClO3 + Heat → 2 KCl + 3 O2
(d) Magnesium nitride reacts with water to produce magnesium hydroxide and ammonia gas.
Mg3N2 + 6 H2O → 3 Mg(OH)2 + 2 NH3
(e) When steam is passed over red hot iron, H2 and Fe3
O4 are formed.
3 Fe + 4 H2O → Fe3O4 + 4 H2
(f) On heating, first hydrated CuSO4 loses water to form anhydrous copper sulphate.
CuSO4.5H2O + Heat → CuSO4 + 5 H2O
- Upon strong heating, anhydrous CuSO4 gets decomposed and CuO, SO2 and O2 are formed.
2 CuSO4 + Heat → 2 CuO + 2 SO2 + O2
(g) When gold particles are put in hydrochloric acid, no reaction takes place.
Answer:
The following reactions happen for the following:
(a) On heating, first FeSO4 loses water to form anhydrous ferrous sulphate.
FeSO4.xH2O + Heat → FeSO4 + xH2O
- Upon strong heating, anhydrous FeSO4 gets decomposed and Fe2O3, SO2 and SO3 are formed.
2 FeSO4 + Heat → Fe2O3 + SO2 + SO3
(b) When lead nitrate is strongly heated, lead oxide, nitrogen dioxide and oxygen are obtained.
2 Pb(NO3)2 + Heat → 2 PbO + 4 NO2 + O2
(c) Potassium chlorate on strong heating decomposes to the potassium chloride and oxygen gas.
2 KClO3 + Heat → 2 KCl + 3 O2
(d) Magnesium nitride reacts with water to produce magnesium hydroxide and ammonia gas.
Mg3N2 + 6 H2O → 3 Mg(OH)2 + 2 NH3
(e) When steam is passed over red hot iron, H2 and Fe3
O4 are formed.
3 Fe + 4 H2O → Fe3O4 + 4 H2
(f) On heating, first hydrated CuSO4 loses water to form anhydrous copper sulphate.
CuSO4.5H2O + Heat → CuSO4 + 5 H2O
eating, anhydrous CuSO4 gets decomposed and CuO, SO2 and O2 are formed.
2 CuSO4 + Heat → 2 CuO + 2 SO2 + O2
(g) When gold particles are put in hydrochloric acid, no reaction takes place.
Explanation: