Question

With the help of chemical reaction, what happens when al is found with CCl₄ in the presence of aqueous NaOH?

a) Assertion: Al undergoes oxidation to form Al₂O₃.

b) Reason: Aluminum reacts with CCl₄ to produce aluminum chloride and carbon.

c) Assertion: Aluminum chloride is reduced to Al₂O₃.

d) Reason: Al reacts with CCl₄ to form a complex with aqueous NaOH.

Answer 1

Aluminum reacts with CCl₄ and aqueous NaOH to form sodium aluminate [NaAl(OH)₄] and chloroform (CHCl₃). The reaction pathway is influenced by the aqueous medium and results in compounds different from those in non-aqueous conditions.

Step-by-step explanation:

When aluminum (Al) is found with CCl₄ in the presence of aqueous NaOH, a complex reaction occurs. Aluminum reacts with CCl₄ to form AlCl₃ and chloroform (CHCl₃), while in the presence of aqueous NaOH, aluminum hydroxide Al(OH)₃ is formed as an intermediate. The aluminum hydroxide then further reacts with excess NaOH to form a soluble, stable poly(hydroxo) complex, sodium aluminate [NaAl(OH)₄], which is soluble in water.

The reaction can be summarized as follows:

• 2Al + 6CCl₄ + 8NaOH → 2Na₃Al(OH)₆ + 6CHCl₃

This complex reaction illustrates how the presence of an aqueous medium can facilitate and alter the pathway of the reaction, leading to the formation of different compounds depending on the reagents and conditions.