Question

Write the chemical name for the ionic compound $\mathbf{Zn}\mathbf{}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}$ and mention its molecular weight in brackets after the name.

Answer 1

$\mathbf{Zn}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}$ :

• The chemical name of $\mathbf{Zn}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}$ is zinc nitrate.
• This ionic compound is basically a type of salt, which exists as a white crystalline salt.
• It is highly deliquescent and is soluble in both water and alcohol.
• It is prepared when zinc ($\mathbf{Zn}$) is dissolved in either dilute or concentrated nitric acid (${\mathbf{HNO}}_{\mathbf{3}}$) The reaction for the same is given as;

$\underset{\mathbf{Zinc}}{\mathbf{Zn}}\mathbf{}\mathbf{+}\underset{\mathbf{Nitric}\mathbf{}\mathbf{acid}}{\mathbf{}\mathbf{2}{\mathbf{HNO}}_{\mathbf{3}}\mathbf{\left(}\mathbf{diluted}\mathbf{\right)}}\mathbf{}\mathbf{\to }\underset{\mathbf{Zinc}\mathbf{}\mathbf{nitrate}}{\mathbf{}\mathbf{Zn}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}\mathbf{}}\mathbf{+}\underset{\mathbf{Hydrogen}}{\mathbf{}{\mathbf{H}}_{\mathbf{2}}}$

$\underset{\mathbf{Zinc}}{\mathbf{4}\mathbf{Zn}}\mathbf{}\mathbf{+}\mathbf{}\underset{\mathbf{Nitric}\mathbf{}\mathbf{acid}}{\mathbf{10}{\mathbf{HNO}}_{\mathbf{3}}\mathbf{\left(}\mathbf{concentrated}\mathbf{\right)}\mathbf{}}\mathbf{\to }\underset{\mathbf{Zinc}\mathbf{}\mathbf{nitrate}}{\mathbf{}\mathbf{4}\mathbf{Zn}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}}\mathbf{}\mathbf{+}\mathbf{}\underset{\mathbf{Ammonium}\mathbf{}\mathbf{nitrate}}{{\mathbf{NH}}_{\mathbf{4}}{\mathbf{NO}}_{\mathbf{3}}}\mathbf{}\mathbf{+}\underset{\mathbf{Water}}{\mathbf{}\mathbf{3}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}}$

• It s used in the synthesis of coordination polymers and a mordant n dyeing.
• It is composed of zinc, nitrogen and oxygen with molecular weights of 65.38, 14, and 16 gm/mol respectively.
  Hence the molecular weight of $\mathbf{Zn}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}$ is 189.38 gm/mol [65.38+(14*2)+(16*6)].

Thus, the chemical name and molecular weight for the ionic compound $\mathbf{Zn}{\mathbf{\left(}{\mathbf{NO}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}$ is zinc nitrate (189.38 gm/mol).