16. Chemical Equilibrium

Select correct answer(s) that would yield more products in the following reaction.

CH₄(g) + 4 F₂(g) ⇌ CF₄(g) + 4 HF(g)     ΔH = 38.2 kJ/mol

a) increase pressure                          c) add 0.31 moles of F₂                   e) cool down reaction vessel
b) increase temperature                    d) add some Xenon gas                  f) decrease volume

The following data was collected for the following reaction at equilibrium 

2 A (g) + 3 B (g)  ⇌ C (g)     

At 25 ^oC K is 5.2 x 10^-4 and at 50 ^oC K is 1.7 x 10^-7. Which of the following statements is true?

a) The reaction is exothermic.

b) The reaction is endothermic.

c) The enthalpy change, ΔH, is equal to zero.

d) Not enough information is given. 

CO (g) + H₂O (g) ⇆ CO₂ (g) + H₂ (g)

H₂ (g) + I₂ (g) ⇆ 2 HI (g)

I₂ (g) ⇆ 2 I (g)

After the reaction reaches equilibrium, an inert gas is introduced into the container under conditions of constant volume. Which of the following would you expect to happen?

Consider the reaction below:

CH₄ (g)  +  F₂ (g)  ⇌  CF₄ (g)  + HF (g)   H = + 38.1 KJ/mol

The following changes will shift the equilibrium to the left except one. Which one would not cause a shift to the left?

Consider the following gas reaction of A₂ ( shaded spheres) and B₂ ( unshaded spheres)

A₂ (g)  +  B₂ (g)  ⇌  2 AB (g) 

Which container proceeds more to completion? 

Which direction will the following reaction (in a 10.0 L flask) proceed if a catalyst is added to the system? 

CaCO₃ (s)  ⇌ CaO (s) + CO₂ (g)            K_p = 3.2 x 10^-28

H₂ (g) + I₂ (g) ⇆ 2 HI (g)      ΔH = –9.42 kJ

At 26°C K_p = 2.3 x 10^–12 and at 56°C K_p = 3.7 x 10^–5 for the hypothetical reaction. Determine if the reaction is endothermic or exothermic.

AB(s) + 2 B(g) ⇌ 3 BB (g) + C (g)