Question

Consider the following chemical reaction at equilibrium. H2SO4(aq) mc011-1.jpg 2H+(aq) + SO42–(aq) The addition of which compound will cause a shift in equilibrium because of a common ion effect? NaCl KNO3 MgSO4 FeCl3

Answer 1

The answer is MgSO₄.

That is in the equation shown below:

H₂SO₄(aq) ------> 2H⁺(aq) + SO₄²⁻

the addition of MgSO₄ will cause a shift in equilibrium because of a common ion effect.

As when MgSO₄ dissociates it gives Mg²⁺ and SO₄²⁻, so there will be more SO₄²⁻ than H⁺, so equilibrium will shift towards left.

MgSO₄(aq) ------> Mg²⁺(aq) + SO₄²⁻.