Question

Write the net ionic equation for the CrO42 ion/CrO7^2 ion equilibrium.

1) what if any experimental evidence do you have that the equilibrium is affected by the addition of H2SO4 solution.

2)are your observation and explanation in (1) consistent with Le Chatelier's principle.

Answer 1

The overall reaction:

Q1.

CrO4^2-(aq) + 2H+ (aq) <-> 2CrO7^2- (aq) + H2O(l)

experimental evidence ----> you will expect to see a change in colo of solution

CrO4² --> yellow

CrO7^2- ---> orange/red

when you add H2SO4 --> H+ ions... the reactants increase in consentration some aqueous CrO42- will react to form more CrO7-2 (orange)

Q2.

this is consistent with the principle of Le Chatelier, since more reactants will make the equilibrium to shift toward more produciton of products, i.e. CrO72- ions