Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.

Start Practicing

Worksheet: Calculating Reaction Quotients from Concentrations

Q1:

At 5 0 0 C , nitrogen and hydrogen react to form ammonia according to the equation: An equilibrium mixture of N H ( ) , H ( ) , a n d N ( ) 3 2 2 g g g at 5 0 0 C was found to contain 1.35 M H 2 , 1.15 M N 2 , and 4 . 1 2 × 1 0 1 M N H . 3 Given that the concentrations of all species are 1.00 M under standard conditions, calculate the equilibrium constant for this reaction.

  • A16.7
  • B0.265
  • C3.77
  • D 6 . 0 0 × 1 0 2
  • E 9 . 2 2 × 1 0 2

Q2:

A reaction is represented by this equation: Which of the following is the correct expression for the equilibrium constant?

  • A 𝐾 = [ ] [ ] [ ] c A B C
  • B 𝐾 = [ [ ] [ ] c C ] A B
  • C 𝐾 = [ ] [ ] [ ] c A B C
  • D 𝐾 = [ ] [ ] [ ] c C A B
  • E 𝐾 = [ ] [ ] [ ] c A B C

Q3:

Water gas, a mixture of H 2 and C O , is an important industrial fuel produced by the reaction of steam with red hot coke, which is essentially pure carbon:

Which of the following is the correct expression for the equilibrium constant ( 𝐾 c ) for the reaction?

  • A 𝐾 c = [ ] [ ] [ ] H O H C O 2 2
  • B 𝐾 c = [ ] [ ] [ ] [ ] H C O C H O 2 2
  • C 𝐾 c = [ ] [ ] [ ] [ ] C H O H C O 2 2
  • D 𝐾 c = [ ] [ ] [ ] H C O H O 2 2
  • E 𝐾 c = [ C ] [ H O ] [ H ] [ C O ] 2 2

Q4:

A 0.72 mol sample of P C l 5 is heated in a 1.00 L vessel. At equilibrium, the vessel contains 0.40 mol of P C l ( ) 3 g and 0.40 mol of C l ( ) 2 g . If the concentrations of all species are 1.00 M under standard conditions, calculate the equilibrium constant, 𝐾 c , for the decomposition of P C l 5 to P C l 3 and C l 2 at this temperature.

Q5:

Water gas is a 1 1 mixture of carbon monoxide and hydrogen gas and is called water gas because it is formed from steam and hot carbon in the following reaction:

Methanol, a liquid fuel that could possibly replace gasoline, can be prepared from water gas and hydrogen at high temperature and pressure in the presence of a suitable catalyst according to the equation

Which of the following is the correct expression for the equilibrium constant ( 𝐾 c ) for this reaction?

  • A 𝐾 c = [ ] [ ] [ ] C H O H H C O 3 2
  • B 𝐾 c = [ ] [ ] [ ] H C O C H O H 2 3 2
  • C 𝐾 c = [ ] 2 [ ] [ ] C H O H H C O 3 2
  • D 𝐾 c = [ ] [ ] [ ] C H O H H C O 3 2 2
  • E 𝐾 c = [ C H O H ] [ H ] [ C O ] 3 2 2