Question

Write a balanced net ionic equation to describe dissolving Fe(OH)2 in hydrochloric acid

a balanced net ionic equation to describe adding excess NH₃ to a basic solution containing Ni²⁺ forming a complex ion.

a balanced net ionic equation to describe the formation of a complex ion of aluminum in a basic solution

balanced net ionic equation to describe the test confirming the presence of Fe³⁺

Answer 1

1. Fe(OH)_2(s) + 2HCl_(aq) ------------> FeCl_2(aq) + 2H₂O_(l)

Fe(OH)_2(s) + 2H⁺_(aq) + 2Cl^-_(aq) ----------> Fe²⁺_(aq) + 2Cl^-_{(aq) +} H₂O_(l)

Fe(OH)_2(s) + 2H⁺_(aq) ----------> Fe²⁺_{(aq) +} 2H₂O_(l)

2. Adding excess NH₃ to Ni²⁺ results in formation of a soluble deep blue Ni(NH₃)₆²⁺ complex:

Ni²⁺(aq) + 6 NH₃(aq) => Ni(NH₃)₆²⁺(aq)

3. Adding excess OH^- to Al³⁺ results in the formation of a soluble colorless Al(OH)₄^- complex:

Al³⁺(aq) + 4 OH^-(aq) => Al(OH)₄^-(aq)

4. Adding SCN^- to Fe³⁺ results in the formation of a soluble blood red FeSCN²⁺ complex:

Fe³⁺(aq) + SCN^-(aq) => FeSCN²⁺(aq)

Hope this helps