passwella.
Menu

JAMB Chemistry 1983 Question 47

Question 47

Chemical Equilibrium

The equilibrium reaction between copper (I) chloride and chlorine at 25°C and 1 atmosphere is represented by the equation: 2CuCl + Cl2 ⇌ 2CuCl2, ΔH = −166 kJ. Which of the following statements is TRUE for the reaction, pressure remaining constant?

  1. A.more CuCl2 is formed at 40°C.
  2. B.More CuCl2 is formed at 10°C.
  3. C.Less CuCl2 is formed at 10°C.
  4. D.There is no change in the amount of CuCl2 formed at 40°C and 10°C.
  5. E.More CuCl is consumed at 40°C.
Show the answer and explanation

Answer: B (More CuCl2 is formed at 10°C.)

Explanation

The forward reaction is exothermic, so lowering the temperature (to 10°C) shifts the equilibrium to the right and more CuCl2 forms.