Home
Class 12
CHEMISTRY
An excess of potassium ions makes KCL...

An excess of potassium ions makes KCL crystals appear violet or lilac in colour since …………. .

A

some of the anionic sites are occupied by an unpaired electron

B

some of the anionic sites are occupied by a pair of electrons

C

there are vacancies at some anionic sites

D

F-centres are created which impart colour to the crystals.

Text Solution

Verified by Experts

The correct Answer is:
A, D
Promotional Banner

Similar Questions

Explore conceptually related problems

An excess of potassium ions makes KCl crystal appear violet or lilac in colour since-

What makes the crystal of KCl sometimes appear pink and how?

Why does KCl turn violet on heating in the potassium vapours ?

Use of an artificial kidney during hemodialysis may result in : Nitrogenous waste build-up in the body Non-elimination of excess potassium ions Reduced 'absorption of calcium ions from gastro-intestinal tract Reduced RBC production Which of the following options is the most appropriate ?

Why does LiCl crystal containing excess lithium ions show pink colour?

When a chromite ore (A) is fused with sodium carbonate in free excess of air and the product is dissolved in water, yellow solution of a compound (B) is obtained. After treatment of this yellow solution with sulphuric acid, compound (C ) can be crystallised from the solution. When compound (C ) is treated with KCl, orange crystals of compound (D ) crystallise out. Identify (A) to (D) and also explain the reactions.

A red solid is insoluble in water. However it becomes soluble if some KI is added to water. On heating the red solid in a test tube, there is liberation of some violet coloured fumes and droplets of a metal appear on the cooler parts of the test tube. The red solid is :

Alkali metals on combustion in excess of air form different type of oxides depending on the size of metal cations e.g . lithium forms mainly the oxide Li_2O , sodium forms peroxide and some super oxides NaO_2 and potassium, Rubidium and caesium form the superoxides, MO_2 . The stability of peroxide and superoxide increases, as the size of the metal cation increases because of the stabilisation of larger anion by larger cations through lattice energy effect. These oxides are easily hydrolysed by water. The oxides and the peroxides are colourless when pure, but the superoxides are yellow or orange in colour. Peroxide and superoxide of sodium and potassium are widely used as oxidising agent and as air purifier in space capsules, submarines and breathing mask. When sodium reacts with excess of oxygen at 350^@ C , the oxidation number of oxygen per atom changes from:

Alkali metals on combustion in excess of air form different type of oxides depending on the size of metal cations e.g . lithium forms mainly the oxide Li_2O , sodium forms peroxide and some super oxides NaO_2 and potassium, Rubidium and caesium form the superoxides, MO_2 . The stability of peroxide and superoxide increases, as the size of the metal cation increases because of the stabilisation of larger anion by larger cations through lattice energy effect. These oxides are easily hydrolysed by water. The oxides and the peroxides are colourless when pure, but the superoxides are yellow or orange in colour. Peroxide and superoxide of sodium and potassium are widely used as oxidising agent and as air purifier in space capsules, submarines and breathing mask. Which of the following compound is used in the emergency breathing apparatus ?