Correct Answer - Option 2 : kieselguhr
Concept:
Quartz, tridymite and cristobalite are crystalline forms of silica. While kieselguhr is an amorphous form of silica.
The diatomaceous is also called as kieselguhr. Diatomaceous earth also known as diatomite or kieselguhr it is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. Depending on the granularity, this powder can have an abrasive feel, similar to pumice powder, and has a low density as a result of its high porosity.
Diatomaceous earth consists of fossilized remains of diatoms, a type of hard-shelled protist. It is used as a filtration aid, mild abrasive in products including metal polishes and toothpaste, mechanical insecticide, absorbent for liquids, matting agent for coatings, reinforcing filler in plastics and rubber, anti-block in plastic films, porous support for chemical catalysts, cat litter activator in blood clotting studies, a stabilizing component of dynamite, a thermal insulator, and a soil for potted plants and trees like bonsai.
