Question

The heat of reaction for c10h8 (s) + 12o2 (g) 10 co2 (g) + 4h2o () at constant volume is -1228.2 kcal at 25 oc. the heat of reaction at constant pressure and the same temperature is

Answer 1

Heat of reaction at constant pressure is represented by ∆H

Heat of reaction at constant volume is represented by∆U

Given​: ∆U = -1228.2 kcal

Since ∆H = ∆U + ∆nRT

In the given reaction ∆n = 10-12 = -2
R = 2 cal/mol K

∆H = -1228.2 +(-2/1000)(2*298) = -1229.4 kcal

Answer 2

Answer:

-1229.392

Explanation:

∆H=∆E +∆ngRT

∆H= -1228.2+[(-2)(2/1000)(298)]

= -1228.2+(-1.192)

= -1229.392

• -2 is the mole difference is gases is product and reactant.
• R=2 cal/mol K
• 25+273=298K