Question

If each ml of a solution of H2PO3 contains the equivalent of 0.5000 M of dissolved P2O5, what vol. of 2.50 M NaOH would be required to react with 20.0 ml of the acid to form HPO4?

Answer 1

Thought the basicity of h3p04 is greater than h3p03, it doesn't mean that it's acidic strength is greater..Like a person who has lots of money doesn't mean that he is giving…

According to the above rule mentioned…h3po4 has 1 oxygen bonded atom and 3 OH- groups so ratio is 1/3

Similarly h3p03 has 1 double bonded oxygen and 2 OH- groups so ratio is 1/2

Since 1/2 > 1/3 …h3po3 has more acidic strength

But if we look other oxyacids of phosphorus

The trend would be HPO3 > H3PO2 > H3PO3 > H3PO4 (check the structures )