Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous 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.
(a) (i) only (b) (ii) only
(c) (i) and (iv) (d) (ii) and (iii)
Ans. (c)
In beaker A:
In beaker B:
Both are exothermic processes. These will increase the temperature
In beaker C:
This is an endothermic process and this will decrease the temperature.