Question

The formula of Prussian blue is :

a.) Na4[Fe(CN)6]

b.) Fe(CN)2

c.) Fe(CNS)3

d.) Fe4[Fe(CN)6]3

Answer 1

`\tt c.)\:\: Fe_4[Fe(CN)_6]_3`

Step-by-step explanation:

Prussian blue is a dark blue pigment that is produced by the oxidation of ferrous ferrocyanide salts. The chemical formula for Prussian blue is

`\tt \bold{Fe_4[Fe(CN)_6]_3}`

This formula shows that Prussian blue is a complex compound that contains four iron atoms, six cyanide ions, and three ferrocyanide ions.

The other options are incorrect.

• 
  `\textsf{Option a.) }\tt Na_4[Fe(CN)_6] \text{is the formula for sodium ferrocyanide}`
• 
  `\tt \textsf{Option b.)} Fe(CN)_2 \text{is the formula for ferrous cyanide}`
• 
  `\tt \textsf{Option c.)} Fe(CNS)_3\text{ is the formula for ferric thiocyanate}`

Therefore, the correct formula for Prussian blue is
`\tt Fe_4[Fe(CN)_6]_3`