Question

Question 10.17 What happens when
(i) magnesium is burnt in air

(ii) quick lime is heated with silica

(iii) chlorine reacts with slaked lime

(iv) calcium nitrate is heated ?

Class XI The s-Block Elements Page 306

Answer 1

(i) magnesium is burnt in air,
2Mg + O2 --->2MgO and
3Mg + N2 ----> Mg3N2

(ii) quicklime is heated with silica.
CaO(quick lime) + SiO2(silica) --->CaSiO3 (calcium silicate)

(iii) Chlorine react with slacklime,
it reacts with Cl2 to form calcium hypochlorite Ca(OCl)2 -a constituent of bleaching powder.
2Ca(OH)2 + 2Cl2 --->{CaCl2 + Ca(OCl)2}-bleaching powder + 2H2O


(iv) calcium nitrate is heated ,
2Ca(NO3)2 ---->2CaO + 4NO2 + O2