Certain crystals produce electric signals on application of pressure. This phenomenon is called

Which of the following is the composition of glass?

Which of the following is an example of an ionic solid?

State the uses of amorphous solids and describe the cleavage property of amorphous solids.

For amorphous solids,select the correct option using $T$ (True) or $F$ (False) for the following statements:
$(1)$ They soften over a range of temperature.
$(2)$ Their physical properties like electrical conductivity and thermal conductivity are the same in all directions.
$(3)$ The arrangement of their particles is disordered.
$(4)$ They are hard and are less affected by pressure.

If a non-metal is added to the interstitial sites of a metal,then the metal becomes: