Question

From the equation : (NH4)2 Cr2O7 ⟶ Cr2O3 + 4H2O + N2 Calculate :
(i) the vol. of nitrogen at STP, evolved when 63 g. of ammonium dichromate is heated.
(ii) the mass of Cr2O3 formed at the same time.
[N = 14, H = 1, Cr = 52, O = 16]

August 5, 2024

Answer

(NH₄)₂Cr₂O₇ ${\overset{ \triangle }{\longrightarrow}}$ Cr₂O₃ + 4H₂O + N₂

252 g 152 g 22.4 lit

252 g of ammonium dichromate gives 22.4 lit of nitrogen

∴ 63 g of ammonium dichromate will give = $22.4\over252$ × 63

= 5.6 lit of nitrogen.

Hence, 5.6 lit of nitrogen is evolved.

(ii) 252 g of ammonium dichromate gives 152 g Cr₂O₃

∴ 63 g of ammonium dichromate will give = $152\over252$ × 63

= 38 g

Hence, 38 g of Cr₂O₃ is formed.

💡 Some Related Questions

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What mass of copper hydroxide is precipitated by using 200 g of sodium hydroxide.
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