Question

34. (i) Name the gas evolved when sodium hydrogen carbonate reacts with dilute hydrochloric acid. Hon will you test the
presence of this gas? (1) A substance Y, which is an oxide of a metal is used extensively in the cement industry. The
element present in the substance X is an important constituent of our bones. On treatment with water, it forms a
solution which turns red litmus blue. Identify 'X' and also write the equation for its chemical reaction with water.
(1) Why is concentrated acid added to water and not water to concentrated acid to make dilute solution of acid?
​

Answer 1

Step-by-step explanation:

(1) Why is concentrated acid added to water and not water to concentrated acid to make dilute solution of acid?

Ans. Dilution of concentrated acid is an exothermic process. If water is added to a concentrated acid, the heat generated may cause the mixture to splash out and cause burns. When the acid is added to water slowly with constant stirring, the mixture will not splash out.