When FeCl ₃ is added to excess of hot water gives a sol ' X '. When FeCl ₃ is added to NaOH (a q) solution, gives sol ' Y ' X and Y formed in the above processes respectively are

Step-by-step solution

When FeCl ₃ is added to an excess of hot water, it hydrolyses to form a sol ' X ' containing Fe ₂ O ₃ x H ₂ O and Fe ³⁺ ions. FeCl ₂+ H ₂ O Fe ₂ O ₃ x H ₂ O Fe ³⁺+2 Cl ⁻ When FeCl ₃ is added to NaOH ( aq ) solution, a precipitation reaction occurs. The Fe ³⁺ ions from FeCl ₃ react with OH ⁻ ions from NaOH to form brown precipitate of Fe ( OH )₃ . This brown precipitate forms a sol ' Y ' containing Fe ₂ O ₃ x H ₂ O and OH ⁻ ions. FeCl ₃+3 NaOH Fe ₂ O ₃ x H ₂ O / OH ⁻+3 NaCl