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 the case of beaker C, the temperature of the solution falls. Which one of the following statements(s) is(are) correct?
(i) In beakers A and B, the exothermic process has occurred.
(ii) In beakers A and B, the endothermic process has occurred.
(iii) In beaker C exothermic process has occurred.
(iv) In beaker C endothermic process has occurred.
(a) (i) only
(b) (ii) only
(c) (i) and (iv)
(d) (ii) and (iii)
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 the case of beaker C, the temperature of the solution falls. Which one of the following statements(s) is(are) correct?
(i) In beakers A and B, the exothermic process has occurred.
(ii) In beakers A and B, the endothermic process has occurred.
(iii) In beaker C exothermic process has occurred.
(iv) In beaker C endothermic process has occurred.
(a) (i) only
(b) (ii) only
(c) (i) and (iv)
(d) (ii) and (iii)

Answer: Answer is (c) (i) and (iv)

Exothermic processes result in the release of enormous amounts of heat – as a result, when water reacts with quick lime and when acid reacts with water, heat energy is released.Exothermic processes cause the temperature to rise, whereas endothermic processes cause the temperature to fall.