The time taken for a calorimeter containing 75 g of water at 62 ° C to cool to 58 ° C is 9 minutes. When the calorimeter contains 105 g of water, it takes 12 minutes to cool from 62 ° C to 58 ° C . The water equivalent of the calorimeter is______

Step-by-step solution

The equation of water equivalent in the first case is, m c d T d t = - k T 1 + T 2 2 - T 0 ⇒ 75 + x c 62 - 58 9 = - k 62 + 58 2 - T 0 . . . . 1 is the second case the equation of water equivalent, ⇒ 105 + x c 62 - 58 12 = - k 62 + 58 2 - T 0 . . . 2 75 + x 9 = 75 + x 12 ⇒ x = 15   g