Question

What is observed when hot concentrated caustic soda solution is added to aluminium?

Answer 1

it leads to the evolution of bubbles of hydrogen gas and results I  formation of sodium aluminate.

Answer 2

Answer:

When hot concentrated caustic soda is added to aluminium, the formation of Sodium Aluminate is seen which is a soluble salt along with hydrogen gas being liberated.

Explanation:

Equation:

2Al    +    6NaOH    →     $2Na_{3} AlO_{3}$   +     3 $H_{2}$

                                 Sodium Aluminate

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