Three beakers labelled as `A, B` and `C` each containing `25` mL of water were taken. A small amount of `NaOH`, anhydrous `CuSO_(4)` 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 ?
(i) In beakers `A` and `B`, exothermic process has occurred.
(ii) In beakers `A` and `B`, endothermic process has occurred.
(iii) In beaker `C`, exothermic process has occurred.
(iv) In beaker `C`, endothermic process has occurred.

Options

A. (i) only
B. (ii) only
C. (i) and (iv)
D. (ii) and (iii)

Answer

C

Explanation

Exothermic reactions have occurred in beakers A and B while reaction taking place in beaker C is of endothermic nature.