Question

When a 0.740-g sample of trinitrotoluene (TNT), C7H5N2O6, is burned in a bomb calorimeter, the temperature increases from 23.4 to 26.9 C the heat capacity of t he calorimeter is 534 j/C, and it contains 675 mL of water. How much heat was produced by the combusttion of the TNT sample?

Answer 1

Explanation:

The given data is as follows.

         mass of sample (X) = 0.740 g,        $T_{1}$ = $23.4 ^{o}C$    

   $T_{1}$ = $26.9 ^{o}C$    

As,   Density = $\frac{mass}{volume}$

              1.00 g/ml = $\frac{mass}{675 ml}$

                  mass = 675 g

Hence, weight of water = 675 g and heat capacity is given as 534 $J/ ^{o}C$

Heat produced by combustion of TNT = Heat gained by the water

             $W \times C \times \Delta T$ = $X \times Heat$

                       Heat = $\frac{W \times C \times \Delta T}{X}$

                                 = $\frac{675 g \times 534 J/C \times (26.6 - 23.4)^{o}C}{0.740 g}$

                                 = 1704831 J

As 1 kJ = 1000 J. So, 1704831 J = 1704.831 kJ

Thus, we can conclude that heat produced by the combustion of the TNT sample is 1704.831 kJ.