Question

What happens when (write reaction only)
A. Steam is passed over hot aluminium.
B. iron (III) oxide ($F{e_2}{O_3}$) heated with a reactive metal Aluminium.

Answer 1

Hint: When steam is passed over hot aluminium, a gas is evolved which burns with a pop sound and an oxide of aluminium is formed. When iron (III) oxide is heated with reactive metal aluminium, the aluminum reduces the iron in the ferric oxide.

Complete step by step answer: Solution: Let us solve the sub questions one by one.
(i) When hot steam is passed over hot aluminium, aluminium oxide is formed and a gas is released with a pop sound. This pop sound marks the release of hydrogen gas. The reaction that takes place is:
\[2Al + 3{H_2}O \to A{l_2}{O_3} + 3{H_2}\]
The aluminium oxide formed as the product in the reaction is an amphoteric substance which means that it can react with both acids and bases, such as hydrochloric acid and potassium hydroxide, acting as an acid with a base and a base with an acid, thus, neutralizing the other and producing a salt with the release of a water molecule.
(ii) When iron (III) oxide ($F{e_2}{O_3}$) is heated with a reactive metal aluminium, the aluminium being at an upper position than the iron, easily displaces iron from its oxide and forms aluminium oxide. The reaction that takes place is:
$F{e_2}{O_3}(s) + 2Al(s)\xrightarrow{\Delta }2Fe(l) + A{l_2}{O_3}(s)$
The iron that is formed in the reaction gets melted due to the rigorous heat that is produced in the reaction.

Note: When iron (III) oxide is heated with aluminium, this process is known as thermite process and is employed for gaining a pure metal by the removal of the impurities from its ore or alloy mixture. The heat generated is sufficient to melt the iron and the aluminum oxide.