Home
Class 11
CHEMISTRY
When an alkali metal dissolves in liquid...

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

Text Solution

Verified by Experts

The dilute solution of alkali metals in liquid ammonia exhibits dark blue colour because ammoniated electrons absorb energy corresponding to the red region of the visible light.
`M+(x+y)NH_(3)to underset("Ammoniated metal ion")([M(NH_(3))_(x)]^(o+))+underset("Ammoniated electron")(e^(-)(NH_(3))_(y)`
However, if the concentration increases above `3 M`,the colour changes to copper-bronze and the solution acquires metallic lustre due to the formation of metal ion clusters.
Promotional Banner

Topper's Solved these Questions

  • APPENDIX - INORGANIC VOLUME 1

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercise very short|70 Videos
  • APPENDIX - INORGANIC VOLUME 1

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercise Short|146 Videos
  • ALKYNES

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercises (Archives - Analytical and Desriptive Type)|4 Videos
  • ATOMIC STRUCTURE

    CENGAGE CHEMISTRY ENGLISH|Exercise Concept Applicationexercise(4.3)|19 Videos

Similar Questions

Explore conceptually related problems

The alkali metals dissolve in liquid NH_(3) , it is found that:

Alkali metals oxide are obtained by combustion of the metals.Although Na normally gives Na_2O_2 ,it will take up further oxygen at elevated pressure and temperature to form NaO_2 .The per and superoxides of the heavier alkalies can also be prepared by passing stoichiometric amounts of oxygen into their solution in liquid ammonia. The different alkali metal oxides can be distinguished by reaction with water.The superoxides reacts with CO_2 and give oxygen gas.The stability of per and superoxides is based upon that larger cation can stablise larger anion, due to larger lattice energy. Alkali metals dissolve in liquid ammonia.Dilute solutions are dark blue in colour but as the concentration increases above 3M, the colour changes to copper bronze and the solution acquires the metallic lusture due to the formation of metal ions clusters.The solutions of alkali metals in liquid ammonia are good conductors of electricity due to the presence of ammoniated cations and ammoniated electrons.However, the conductivity decreases as the concentrations increases, since ammoniated electrons and ammoniated cation associate. On dissolving smaller (less than 3M) amount of sodium metal in liquid ammonia at low temperature , which one of the following does not occur ?

Alkali metals oxide are obtained by combustion of the metals.Although Na normally gives Na_2O_2 ,it will take up further oxygen at elevated pressure and temperature to form NaO_2 .The per and superoxides of the heavier alkalies can also be prepared by passing stoichiometric amounts of oxygen into their solution in liquid ammonia. The different alkali metal oxides can be distinguished by reaction with water.The superoxides reacts with CO_2 and give oxygen gas.The stability of per and superoxides is based upon that larger cation can stablise larger anion, due to larger lattice energy. Alkali metals dissolve in liquid ammonia.Dilute solutions are dark blue in colour but as the concentration increases above 3M, the colour changes to copper bronze and the solution acquires the metallic lusture due to the formation of metal ions clusters.The solutions of alkali metals in liquid ammonia are good conductors of electricity due to the presence of ammoniated cations and ammoniated electrons.However, the conductivity decreases as the concentrations increases, since ammoniated electrons and ammoniated cation associate. Solution of sodium metals in liquid ammonia is strongly reducing due to the presence of :

Alkali metals oxide are obtained by combustion of the metals.Although Na normally gives Na_2O_2 ,it will take up further oxygen at elevated pressure and temperature to form NaO_2 .The per and superoxides of the heavier alkalies can also be prepared by passing stoichiometric amounts of oxygen into their solution in liquid ammonia. The different alkali metal oxides can be distinguished by reaction with water.The superoxides reacts with CO_2 and give oxygen gas.The stability of per and superoxides is based upon that larger cation can stablise larger anion, due to larger lattice energy. Alkali metals dissolve in liquid ammonia.Dilute solutions are dark blue in colour but as the concentration increases above 3M, the colour changes to copper bronze and the solution acquires the metallic lusture due to the formation of metal ions clusters.The solutions of alkali metals in liquid ammonia are good conductors of electricity due to the presence of ammoniated cations and ammoniated electrons.However, the conductivity decreases as the concentrations increases, since ammoniated electrons and ammoniated cation associate. Select the correct choice for alkali metal oxides.

Alkali metals oxide are obtained by combustion of the metals.Although Na normally gives Na_2O_2 ,it will take up further oxygen at elevated pressure and temperature to form NaO_2 .The per and superoxides of the heavier alkalies can also be prepared by passing stoichiometric amounts of oxygen into their solution in liquid ammonia. The different alkali metal oxides can be distinguished by reaction with water.The superoxides reacts with CO_2 and give oxygen gas.The stability of per and superoxides is based upon that larger cation can stablise larger anion, due to larger lattice energy. Alkali metals dissolve in liquid ammonia.Dilute solutions are dark blue in colour but as the concentration increases above 3M, the colour changes to copper bronze and the solution acquires the metallic lusture due to the formation of metal ions clusters.The solutions of alkali metals in liquid ammonia are good conductors of electricity due to the presence of ammoniated cations and ammoniated electrons.However, the conductivity decreases as the concentrations increases, since ammoniated electrons and ammoniated cation associate. KO_2 is used in oxygen cylinders in space and submarines because it :

When alkali metal is dissolved in liquid NH_3 the blue colour of the dilute solution changes to bronze colour due to

When sodium is dissolved in liquid ammonia, a solution of deep blue colour is obtained. The colour of the solution is due to

When sodium is dissolved in liquid ammonia, a solution of deep blue colour is obtained. The colour of the solution is due to

Sodium metal dissolves in liquid ammonia and forms a deep blue solution. The colour is due to absorption of light by :

Why is the solution of an alkali metal in ammonia blue?