ZnO turns yellow on heating. Why?

In ZnO , Zn + 2 ions occupy the interstitial sites and electrons are trapped in the interstitial sites for neutralization. Crystals that show such type of defects are generally coloured. Zinc oxide is white in colour at room temperature. On heating, it loses oxygen and turns yellow.

E M B I B E

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 14

MEDIUM

11th CBSE

IMPORTANT

Earn 100

Draw the structures of $CsCl$ and represent the coordination numbers of ${Cs}^{+}$ and ${Cl}^{-}$ ions in the diagram.

Important Questions on States of Matter: Solid State

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 16

Define radius-ratio. What is the coordination number if the radius ratio of the compound is

0.52

?

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 17

Define radius ratio. What is the value of radius ratio for octahedral geometry?

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 20

Derive an expression for the calculation of density of the cubic crystal of an element whose edge is

' a' pm

and atomic mass is

M

.

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 23

What is the difference between 'Schottky defects' and 'Frenkel defects'?

MEDIUM

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 24

Explain the nature of crystal defect produced when sodium chloride is doped with magnesium chloride.

EASY

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 32

Explain Schottky defect in ionic crystal. What type of compounds exhibit this?

MEDIUM

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 33

How would you account for the following?

Frenkel defects are not found in alkali metal halides.

HARD

11th CBSE

IMPORTANT

Pradeep's Chemistry Vol 1>Chapter 6 - States of Matter: Solid State>ADDITIONAL QUESTIONS>Q 35

Solids can be classified into three types on the basis of their electrical conductivities.
Name three types of solids classified on the basis of electrical conductivities.