Question

an alkali metal A gives a compound B(molecular mass=40) on reacting with water.The compound B gives a soluble compound C on treatment with aluminium oxide.Identify A,B, and C and give the reactions involved

Answer 1

The balanced Chemical equation is :

2H2  + O2 ----->2H20

Molar mass of H2=2g
Molar mass of O2=32g
Molar mass of H2O=36g

∴ 4g Of hydrogen reacts with 32g of oxygen to produce 36g of water.

4g of Hydrogen ----> 36g Of water.
10g Of Hydrogen ----> ?
=10x36/4
=90 grams

∴10g Of  H2  will produce 90 grams of water