Do all solids expand on heating? Name the solid that contracts on heating

Name two solid non-metal .

For each of the given solid, the two views are given. Match for each solid the corresponding top and front views.

For each of the given solid, the two views are given. Match for each solid the corresponding top and front views. The first one is done for joy.

Do specific heat and latent heat have the same dimensions?

Crystalline solids are not true solids. Why?

Name the two main groups of solids.

Refractive index of a solid is observed to have the same value along all directions. Comment on the nature of this solid. Would it show cleavage property?

Amorphous solids are not true solids. What are they called then?