Which of the following features are not shown by quartz glass? (i) This is a crystalline solid. (ii) Refractive index is the same in all the directions. (iii) This has a definite heat of fusion. (iv) This is also called supercooled liquid.
Since quartz glass is an amorphous solid, it has no definite heat of fusion. This is due to short-range order of molecule. Also known as super cooled liquid, quartz glass is isotropic in nature
