How to obtain pure aluminium oxide from sodium aluminate. pls help.​

By Bayer process.

Explanation:

In the Bayer process, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution (caustic soda) at a temperature of 150 to 200 °C. At these temperatures, the aluminium is dissolved as sodium aluminate (primarily [Al(OH)4]−) in an extraction process.

i think so it’s will be b yes i believe its

1. they vary with a higher number because boiling is way hotter than melting