Question

Which of the following statements are true about quartz?
A. It is pure crystalline form of silica.
B. It is a tetrahedral polymer of $Si{O}_2$
C. UV light can pass through quartz.

• A. A and B are correct
• B. B and C are correct
• C. A and C are correct
• D. All are correct

Answer 1

The correct option is C A and C are correct

Various forms of silica $\left(Si{O}_2\right)$ are quartz, sand, flint, etc.
It is made up of a continuous framework of $Si{O}_4$ silicon oxygen tetrahedra, with each oxygen being shared between two tetrahedra. giving an overall formula $Si{O}_2$
Quartz is a good transmitter of UV rays. Most glasses are opaque to UV. The UV range is from 0.1 nm to about 400 nm (or from $100A^{\circ }$ to about $4000A^{\circ }$) The visible light wavelengths are longer, between 400 nm and 700 nm Quartz will transmit UV from 180 nm to 400 nm. Since quartz is made of slicon dioxide,
glasses made from a high proportion of this material will also readly transmit UV. One such glass is known as VYCOR, which is 96% silica.
So statement A and C are correct.