Question

On addition of Na2CO3 to hard water a) the foaming capacity increases b) the foaming capacity decreases c) the foaming capacity increases then decreases d) the foaming capacity decreases then increases

Answer 1

Na₂CO₃ is added to hard water to remove the hardness from the water. Therefore it will increase the foaming capacity.
∴, The right answer is a).  

Answer 2

Ans is a) the foaming capacity increases.