Are salt crystals really dry? Explain

Presence of excess sodium makes NaCl crystal coloured. Explain on the basis of the crystal defects.

•Take about 2 g ferrous sulphate crystals in a dry bottle tube. • Note the colour of the ferrous sulphate crystals. • Heat the boiling tube over the flame of a burner or spirit lamp as shown in Fig. Observe the colour of the crystals after heating.

How does sprinkling of salt help in clearing the snow covered roads in hilly areas? Explain the phenomenon involved in the process.

CaCl_2 will introduce Schottky defect when added to AgCl crystal. Explain.

Explain why does conductivity of germanium crystals increase on doping with gallium.

It is difficult to burn a heap of green leaves but dry leaves catch fire easily. Explain.