Question

State one chemical test between each of the following pairs:
Ferrous Nitrate and lead nitrate.

Answer 1

We use Sodium Hydroxide, $NaOH$.

1. When Sodium Hydroxide ($NaOH$) is added to Ferrous Nitrate ($Fe{\left(N{O}_3\right)}_3$), we get a dirty green precipitate of Ferrous Hydroxide ($Fe{\left(OH\right)}_2$).

$Fe{{\left(N{O}_3\right)}_3}^{}\left(aq\right)+3NaOH\left(aq\right)\to Fe{\left(OH\right)}_3\left(s\right)+3NaN{O}_3\left(aq\right)$

Ferrous Nitrate Sodium Hydroxide Ferrous Hydroxide Sodium Nitrate

2. When Sodium Hydroxide ($NaOH$) is added to Lead Nitrate ($Pb{\left(N{O}_3\right)}_2$), we get a white precipitate of Lead Hydroxide ($Pb{\left(OH\right)}_2$).

$Pb{\left(N{O}_3\right)}_2\left(aq\right)+2NaOH\left(aq\right)\to Pb{\left(OH\right)}_2\left(s\right)+2NaN{O}_3\left(aq\right)$

Lead Nitrate Sodium Hydroxide Lead Hydroxide Sodium Nitrate

Sodium Hydroxide, $NaOH$, is used to distinguish between Ferrous Nitrate and Lead Nitrate.