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Question
How much calcium oxide is formed when 82g of calcium nitrate is heated? Also find the volume of nitrogen dioxide evolved:
2Ca(NO3)2→ 2CaO + 4NO2 + O2 (Ca = 40,N = 14, O = 16)
Solution
2Ca(NO3)2→ 2CaO + 4NO2 + O2
Molecular weight of 2Ca(NO3)2 = 2 [ 40 + 2( 14 + 48) = 32g
Molecular weight of CaO = 2 (40 + 16) = 112g
328g of Ca(No3)2 liberates 4 moles of NO2
328g of Ca (NO3)2 liberates 4 × 22.4L of NO
82g will librate `[4 xx 22.4]/328` x 82 = 22.4dm3 of NO2
328g of calcium nitrate gives 112g of CaO.
82g will give `[112 xx 82]/328` = 28g of CaO.
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