Question

5 g of a metal carbonate on complete decomposition gives 2.8g of metal oxide. Then equivalent mass of metal will be​

Answer 1

Given - Weight of metal carbonate : 5 gram

Weight of metal oxide : 2.8 gram

Find - Equivalent mass of metal.

Solution - Metal oxide forms in the decomposition reaction of metal carbonate. Therefore, ratio of molecular weight of both will be equal to ratio of equivalent of both the compounds.

Representing it in equational form -

Weight of metal carbonate/ weight of metal oxide = (equivalent mass of metal + equivalent mass of CO3²-)/(equivalent mass of metal + equivalent mass of O²-)

Let the equivalent mass of metal be X.

5/2.8 = (X+30)/(X+8)

5X + 40 = 2.8X + 84

5X - 2.8X = 84 - 40

2.2X = 44

X = 20

Hence, the Equivalent mass of metal will be 20.