Question

(1) The reaction the decomposition of ammonia is shown below. Calculate the total ∆H If bond energies in K/J: N≡N is 944, H-H is 436 and N-H is 388 Reactions: 2 NH3→N_2+3H_2 Explain reason for your answer

(2) Which of the following statements is FALSE and why?

A) Entropy is a state function.

B) Endothermic processes decrease the entropy of surroundings, at constant T and P.

C) Endothermic processes are never spontaneous.

D) Entropy of the surroundings depends on the enthalpy of the system at a constant T.

E) None of the above

(3)

Identify the change in state that does not have an increase in entropy explain reason for your answer.

(A) Vaporization

(B) Sublimation

(C) Dissolving

(D) Deposition

(E) Melting

(4) Calculate ∆G° for the reaction below from formation value given and explain reason for your answer

2NaCI (s) →2Na(s)+CI2(g)

∆Gf° NaCl (s) =-384 KJ/MOl

(5) Which statement is True and why?

a) An exothermic reactions absorbs heat from the surroundings.

B) Enthalpy is the sum of a system’s internal energy and the product of pressure and volume.

C) ∆Grxn is the entropy of reaction.

D) ∆Grxn is a measure of heat.

E) Endothermic relation have a negative sign for ∆H

CHEMISTRY

Answer 1