Question

State why addition of sodium chloride to water is considered a physical change,
while addition of dilute sulphuric acid to zinc is considered a chemical change? ​

Answer 1

Answer:

the reaction of sodium chloride to water is a physical change because sodium chloride (common salt) gets dissolved in Water and no chemical change takes place. The Identity of both water and common salt remains the same.

on the other hand ,the addition of dilute sulphuric acid to zinc is considered a chemical change because a chemical reaction takes place in with sulphuric acid reacts with zinc to form zinc sulphate and hydrogen gas.