Question

Which of the following is most acidic oxide?

a.Na2O
b.Al2O3
c.P2O5
d.SO3
And why it is most acidic oxide?
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Answer 1

-i effect required here

Let's see which oxide shows more -i effect

• Na-Group 1
• Al-Group 15
• P-Group 15
• S -Group 16

P lies below Al

And -i effect increases down the group so acidity increases

• P_2O_5 is more acidic