When an alkali metal dissolves in liquid ammonia the solution can acquire different colours. Explain the reasons for this type of colour change.

Asked by Pragya Singh | 11 months ago |  45

1 Answer

Solution :-

When the alkali metal is dissolved in liquid ammonia, a deep blue coloured solution is formed.

\( M+(x+y)NH_{3}\rightarrow M^{+}(NH_{3})_{x}+e^{-1}(NH_{3})_{y} \)

The ammoniated electrons absorb energy corresponding to red region of visible light. Therefore, the transmitted light is deep blue in colour.

Clusters of metal ions are formed at higher concentration (3M) which causes the solution to attain a copper-bronze colour and a metallic lustre.

Answered by Abhisek | 11 months ago

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