Question

Washing soda has the formula Na2CO3.10H2O. What mass of anhydrous sodium carbonate is left when all the water of crystallization is expelled by heating 57.2 g of washing soda.

August 5, 2024

Answer

Na₂CO₃.10H₂O	→	Na₂CO₃	+	10H₂O
286 g		106 g		180 g

286 g of washing soda had 106 g of anhydrous sodium carbonate

∴ 57.2 g will have = $106\over286$ × 57.2 = 21.2 g anhydrous sodium carbonate.

Hence, 21.2 g anhydrous sodium carbonate is left.

💡 Some Related Questions

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