the value of delta H° for aniline = -3201. 5 Kj/mol
calculation
Step 1: find heat
Q ( heat) = C ( specific heat capacity) x ΔT ( change in temperature)
C= 4.25 kj/c°
ΔT = 69.8-29.5 = 40.3 c°
Q= 4.25 kj/c x 40.3 c = 171.28 kj
Step 2: find the moles of aniline
moles = mass/ molar mass
= 4.98 g/ 93.13 g/mol =0.0535 moles
Step 3 : find delta H
171.28 kj / 0.0535=3201.5 kj/mol
since the reaction is exothermic delta H = -3201.5 Kj/mol
