Question

chemical reaction was performed in a coffee cup calorimeter (the set up you experiment 2). The calorimeter contained 50.0 g of water at an initial temperature After the reaction was complete the temperature of the water was 27.0°C. Coleute a. Calculate the energy change, in joules (J), of the water. The specific heats is 4.18 J/gºC. ater at an initial temperature of 22.0°C. ules ("), of the water. The specific heat (S.H.) of water Page 2 UTOROURUAN b. Identify the reaction as endothermic or exothermic. Please explain why.

Answer 1

a mass of water in the caloniem. eter, m=50 g Initial temperature = 22 °c final temperature = 27°C i Temperature difference AT = (27- 22 °c Given, specific heat of water, s=4.18 J/9.00 Now, we know that - q=m.S.AT = 50 g x 4.18 J. of of x 50% = 1045 J Thus, the energy change of water = 1045 I Ans

Now Heat gained by the water I = Heat lost by the reaction a AH = - 1045 J Thus, heat gained by the water come from the heat produced -by the reaction Hence, the reaction is - L exothermic. Hon