The correct chemical reaction should be:
Fe(OH)2 -> Fe(OH)3 + H2O
Fe(OH)3 + 3 HNO3 -> Fe(NO3)3 + 3 H2O
So,the correct overall reaction is:
Fe(OH)2 + 3 HNO3 -> Fe(NO3)3 + 2 H2O
The correct chemical reaction should be:
Fe(OH)2 -> Fe(OH)3 + H2O
Fe(OH)3 + 3 HNO3 -> Fe(NO3)3 + 3 H2O
So,the correct overall reaction is:
Fe(OH)2 + 3 HNO3 -> Fe(NO3)3 + 2 H2O