Equilibrium Review

When the system X + 2 Y <=> Z has reached equilibrium, which of the following is TRUE?

• Forward reaction and Backward reaction stop.
• Forward reaction has sped up and backward reaction has slowed down.
• Forward and backward reactions occur at the same rate.
• Forward reaction has slowed down and backward reaction has sped up.

At what time the reaction reached equilibrium?

• t₁
• t₂
• t₃
• t₄

For the reaction...
SO₂ + O₂  <=>  SO₃
If the concentration of SO₂ is increased, the equilibrium position of the reaction will shift ___________.

• to the left
• to the right
• to the left and right 
• neither left nor right

For the reaction...
N₂  +  O₂  <=>  2NO
If  O₂ is removed, the  concentration of N₂ will _______.

• increase
• decrease
• remain the same
• double

What is the K_c expression for this reaction?
   2 NO_(g)  +  O_2(g) ⇌  2 NO_2(g)

• K_c = [NO₂]² / [NO]² [O₂]
• K_c =  [NO]² [O₂] / [NO₂]²
• K_c = [NO]² [O₂] [NO₂]²
• K_c = [NO₂]² / [NO]² +  [O₂]

An equilibrium constant with a large value, e.g. K_c = 1000, indicates…

• A very fast reaction
• Product favored at equilibrium

• Reactant favored at equilibrium

• Nothing useful at all

Le Chatelier's Principle states that.... 
If a (dynamic) equilibrium is disturbed by changing the conditions, the position of equilibrium................

• moves to increase the change
• moves to counteract the change
• does not change

What are [A] and [B]?

• concentration of reactants
• concentration of products
• energy of reactants
• energy of products

The following reaction :     SO_{2 (g)} +  NO_{2 (g)} <=> SO_{3 (g)} + NO (g)   had reached a state of equilibrium, was found to contain   0.40 M SO₃ , and 0.30 M NO, 0.15 M NO₂ , and 0.20 M SO₂. Calculate the equilibrium constant  for this reaction. 

• 4
• .42
• .25
• 1

Which of the two graphs reaches equilibrium?

• Neither

• The left

• Both

• The right