Question
Question: A compound is yellow when hot and white when cold. The compound is :...
A compound is yellow when hot and white when cold. The compound is :
A
Al2O3
B
PbO
C
CaO
D
ZnO
Answer
ZnO
Explanation
Solution
It is a white powder which becomes yellow on heating due to change in the structure of lattice (due to cation excess defect) but again turns white on cooling.