Question

When $CO_2$ is passed through solution of sodium aluminate, precipitate of which compound is formed?

• A. $Al(OH)_3$
• B. $Al_2O_3$
• C. $Na_2CO_3$
• D. No ppt

Answer 1

Answer: (A)

$Al(OH)_3$

Answer 2

In Hall?? process, for purifying the bauxite ore, the solution containing sodium meta aluminate is warmed to 50-60$^{\circ}$C and carbon dioxide is circulated through it, Al(OH) separates out as precipitate. ${2NaAlO2 + CO2 + 3H2O -> 2Al(OH)3 + Na2CO3}$