Question

1. The reaction Fecl3 + H20 (cold water)
i. Observation: what is the color of product formed and is it a solution, precipitate or a gelatinous precipitate.
ii. Inference: e.g is any ion present like fe3+, fe2+ etc
2. divide the result of the solution formed above into 2 portions (in 2 test tubes)
3. Take portion ONE and react it with dilute hcl
i. Observation : is there any color change or precipitate formed
ii. inference: What is the inference for the reaction i.e is any ion like fe3+ present or confirmed

Answer 1

The balanced equation for the reaction is

FeCl3 + 3H2O ↔ Fe(OH)3↓ + 3HCl.

Like standard hydrolysis reactions, interaction of iron(III) chloride with water takes place in stages.

First iron(III) chloride dissociates. Then the iron cation interacts with water. Precipitate Fe(OH)3 forms.

Since iron(III) chloride is soluble in water, but not iron(III) hydroxide, the reaction causes a solid to be precipitated. As iron(III) hydroxide is brown, a brown precipitate is formed. Hence, this is known as a precipitation reaction.

The hy­drol­y­sis re­ac­tion of iron(III) chlo­ride takes place re­versibly.

Fe(OH)3↓ + 3HCl ↔ FeCl3 + 3H2O

The precipitate is dissolved. Ion Fe3+ present in the solution.