Please help The following substances undergo complete combustion in a bomb calor
ID: 928124 • Letter: P
Question
Please help The following substances undergo complete combustion in a bomb calorimeter. AThe bomb calorimeter assembly (including the water) has a heat capacity of 4.881 KJ/degree C. In each case, what is the final water temperature if the initial water temperature is 24.62 degree C? 0.5187 grams of cyclohexanol (C_6H_12O_(I)): heat of combustion = -3727 KJ/mol 1.75 mL of ethyl acetate (C_4H_^O_2(I), density = 0.901 g/mL); heat of combustion = -2246 KJ/mol. A 0.50 gram sample of NH_4NO_3 is added to 35.0 grams of water in a "coffee cup" (constant pressure) calorimeter and stirred until it dissolves. The temperature of the solution drops from 22.7 degree C to 21.6 degree C. What is the HEAT OF SOLUTION of NH_4NO_3 expressed in KJ/mol NH_4NO_3?Explanation / Answer
(1)
a. dHcomb = -qrxn
3727 = 4.881 x (Tf - 24.62) x 100.157/0.5187
Tf = 28.57 oC is the final temperature
b. Ethylacetate = 1.75 x 0.901 = 1.57675 g
2246 = 4.881 x (Tf - 24.62) x 88.11/1.57675
Tf = 32.85 oC
(2) qsoln = -35 x 4.184 x (21.6 - 22.7) x 80.052/0.5 = 25.790 kJ/mol
(3) 0.827 x (Tf - 24.98) x 100.158/0.5060 = 3727
Tf = 47.75 oC will be the final temperature