Give the use of diamond.

On heating copper nitrate strongly,$.......$ is finally obtained.

Silver nitrate is prepared by

If in a mineral $1000$ tetrahedral basic unit of silicates are arranged in a chain,then what will be the formula of the anion of that mineral?

Identify the correct statements among the following:
$a$) $C_{60}$ molecule has $12$ five-membered rings and $20$ six-membered rings.
$b$) $H_2CO_3 / HCO_3^-$ buffer system helps to maintain $pH$ of blood between $7.26$ and $7.42$.
$c$) Graphite is used as a dry lubricant in machines running at high temperatures.

Carbon can form $p\pi-p\pi$ bond with which kind of elements?