Question

Predict the formula of a compound formed by aluminium and sulphur.

• A. $A{l}_2{S}_2$
• B. $A{l}_3{S}_2$
• C. $A{l}_2{S}_3$
• D. $AlS$

Answer 1

Answer: (C)

$Al-3e^{-}\to A{l}^{3+}$, $S+2e^{-}\to S^{2-}$
The formula for its sulphide is $A{l}_2{S}_3$