Among `Al_(2)O,SiO_(2),P_(2)O_(3)` and `So_(2)` the correct order of acid strength is

Options

A. `Al_(2)O_(3) lt SiO_(2) lt SO_(2) lt P_(2)O_(3)`
B. `SiO_(2) lt SO_(2) lt Al_(2)O_(3) lt P_(2)O_(3)`
C. `SO_(2) lt P_(2)O_(3) lt SiO_(2) lt Al_(2)O_(3)`
D. `Al_(2)O_(3) lt SiO_(2) lt P_(2)O_(3) lt SO_(2)`

Answer

D

Explanation

With decrease in size from `Al` to `S` the basic nature of oxide decrease and acidic nature increases.
`Al_(2)O_(3) lt SiO_(2) lt P_(2)O_(3) lt SO_(2)`
`Al_(2)O_(3)` is amphoteric, `SiO_(2)` is slightly acidic whereas `P_(2)O_(3)` and `SiO_(2)` are the anhydrides of acids `H_(3)PO_(3)` and `H_(2)SO_(3)`.