Question

How much calcium oxide is obtained by heating 82 g of calcium nitrate? Also, find the volume of NO₂ evolved:

\[\ce{2Ca(NO3)2 ->2CaO + 4NO2 + O2}\]

Answer 1

\[\ce{2Ca(NO3)2 ->2CaO + 4NO2 + O2}\]

Molecular Weight of 2Ca(NO₃)₂ = 2(40 + 28 + 96) = 328 g

Molecular weight of CaO = 2(40 + 16) = 112 g

328 g of Ca(NO₃)₂ forms 112 g of CaO

82 g of Ca(NO₃)₂ forms `112/328 xx 82` = 28 g

328 g of Ca(NO₃)₂ will evolved 4× 22.4 l of NO₂

82 g of Ca(NO₃)₂ will evolve `(4 xx 22.4)/328 xx 82` = 22.4 l