Question

Red mud consists of ferric oxide, sand which are removed by ______.

Options

• distillation

• filtration

• chromatography

• none of these

Answer 1

Red mud consists of ferric oxide, sand which are removed by filtration.

Explanation:

During Baeyer's process, bauxite dissolves in sodium hydroxide, but ferric oxide and sand remain insoluble as "red mud". This insoluble residue is separated from the liquid solution by filtration.