Three beakers labelled as A, B and C each containing 25 mL of water

• GC Chemical Reactions

Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous CuSO₄ and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solutions contained in beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is (are) correct?

1. In beakers A and B, exothermic process has occurred.
2. In beakers A and B, endothermic process has occurred.
3. In beaker C exothermic process has occurred.
4. In beaker C endothermic process has occurred.

Select the correct option:

1. (i) only
2. (ii) only
3. (i) and (iv)
4. (ii) and (iii)

Answer

For an exothermic reaction, heat releases during reaction so temperature increases whereas endothermic reactions proceed with absorption of heat which decrease the temperature of reaction.

The correct option is C.