Assertion (A): To dilute sulphuric acid, acid is added to water and not water to acid. Reason (R): Specific heat of water is quite large.

1. Assertion (A): States the common laboratory safety practice: when diluting concentrated sulphuric acid, the acid should be added slowly to water, not water to acid. This is correct because the dilution process is highly exothermic (releases heat). Adding water to acid can cause the small amount of water to boil violently and splash the concentrated acid out. Adding acid to water ensures the large volume of water can absorb the heat generated more safely. Assertion (A) is true. 2. Reason (R): States that the specific heat of water is quite large. Specific heat capacity is the amount of heat required to raise the temperature of a substance. Water does have a very high specific heat capacity compared to many other substances, including concentrated sulphuric acid. Reason (R) is true. 3. Explanation: The high specific heat of water (Reason R) allows the bulk water to absorb the significant heat released during dilution without a drastic temperature increase, which is why adding acid to water (Assertion A) is the safer procedure. Thus, R is the correct explanation for A. 4. Conclusion: Both A and R are true, and R is the correct explanation of A.