For the reaction
how many kcal are needed to form 2.00 moles
A) 68.5 kcal
B) 548 kcal
C) 190 kcal
D) 274 kcal
E) 137 kcal

Question

For the reaction 
how many kcal are needed to form  2.00  moles 
A) 68.5 kcal 
B) 548 kcal 
C) 190 kcal 
D) 274 kcal 
E) 137 kcal

Quizplus · Accepted Answer

The given reaction is: 
11ec7dc9_9aa8_6c12_8044_9d4ef7ed2d37_TB34225555_11  →  2 11ec7dc9_9aa9_7d83_8044_c1e600140041_TB34225555_11

We need to find the energy required to form 2 moles of product. The enthalpy change for the given reaction is -137 kcal/mol (given in the question).

Using stoichiometry, we can say that the enthalpy change for the formation of 2 moles of product will be:
Enthalpy change for 1 mole X 2 moles = -137 kcal/mol X 2 = -274 kcal

Therefore, the correct answer is D) 274 kcal.

For the Reaction