Question

Small, highly charged metal cations may interact with H2O to give solutions that are not neutral. Which net ionic chemical equation correctly represents the reaction of Cu(NO3)2 with water?
a. Cu2+(aq) + H2O(l) ⇌ Cu(OH)1-(aq) + H+1(aq)
b. Cu2+(aq) + H2O(l) ⇌ Cu(OH)1+(aq) + H+1(aq)
c. Cu2+ (aq) + H2O(l) ⇌ CuH3+(aq) + H1- (aq)

Answer 1

Answer:

Option B is correct.

The net ionic chemical reaction when Cu(NO₃)₂ reacts with water is

Cu²⁺(aq) + H₂O(l) ⇌ Cu(OH)¹⁺(aq) + H¹⁺(aq)

Explanation:

When ions dissolve in polar solvents (in water especially), then often attract ions of opposite signs.

Cu(NO₃)₂ dissolves into Cu²⁺ & NO₃⁻ and water contains H¹⁺ & OH⁻

The Cu²⁺ attracts the OH⁻ from water, thereby giving the Cu(OH)¹⁺ ion (with a net charge of +2-1 = +1) and the NO₃⁻ takes up the H⁺ ion.