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JEE Main20199 Apr 2019Evening ShiftChemistryp Block Elements (Group 13 & 14)Actual

The amorphous form of silica is:

Options

  1. Aquartz
  2. Bkieselguhr
  3. Ctridymite
  4. Dcristobalite

Correct answer

B. kieselguhr

Step-by-step solution

Kieselguhr, an amorphous form of silica is used in filtration plants. Quartz is one of the most common minerals in the earth’s crust having a specific crystalline form. Cristobalite is a high temperature polymorph of silica, having same chemical formula as quartz but distinct crystal structure. Tridymite is also a high temperature polymorph of silica and occurs as hexagonal crystals.

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