Chemistry · D and f Block Elements
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Many hexaaqua complex ions can undergo reaction with water as given below
[Fe(H2O)6]+2 aq + H2O⇌[Fe(H2O)5OH]+ + H3O+
The reaction is classed as:
- A
Redox reaction
- B
Acid base reaction
- C
Substitution reaction
- D
Decomposition reaction
The reaction is ‘decomposition’ as one mole of water is removed to form the hydronium ion
Redox reaction is still incorrect, as there is no transfer of electrons between species.
Acid-base reaction is partially correct, as the reaction does involve the transfer of a proton (H+) between species. However, the primary classification of the reaction is a decomposition reaction.
Substitution reaction is also partially correct, as the reaction does involve the substitution of a water molecule with a hydroxide ion in the complex ion. However, the primary classification of the reaction is a decomposition reaction.
The reaction is 'decomposition' as one mole of water is removed to form the hydronium ion. As it involves the breakdown of the hexaaqua complex ion [Fe(H2O)6]2+ into a new complex ion [Fe(H2O)5OH]+ and a hydronium ion (H3O+).
Tagged under Chemistry · D and f Block Elements · 2017