Home
Class 12
CHEMISTRY
H(3)PO(4) is tribasic while H(3)PO(3) is...

`H_(3)PO_(4)` is tribasic while `H_(3)PO_(3)` is dibasic. Explain.

Text Solution

Verified by Experts

(1) In oxoacids (or oxyacids) of phosphorus, `P-H` bonds being non-polar do not ionise in aqueous solution to give `H^(+)` and hence do not show any basicity or acidic character.
(2) `H^(+)` ions in oxyacids are obtained only from `P-OH` bonds since `O-H` bond is polar. Hence `P-OH` bonds cause basicity. Therefore basicity of oxoacids is equal to number of `P-OH` bonds.
(3) In `H_(3)PO_(4),` there are three `P-OH` bonds hence it is tribasic, while in `H_(3)PO_(3)` there are two `P-OH` bond hence it is dibasic.
Promotional Banner

Similar Questions

Explore conceptually related problems

Statement-1 : Both H_(3)PO_(3) and H_(3)PO_(4) have the same number of hydrogen atoms but H_(3)PO_(4) is a tribasic acid and H_(3)PO_(3) is a dibasic acid. Statement-2 : 1 mol of H_(3)PO_(3) is neutralised by 2 mol of NaOH while 1 mol of H_(3)PO_(4) is neutralised by 3 mol of NaOH

Asseration: Both H_(3)PO_(4) and H_(3)PO_(3) posses the same number of hydrogen atoms, but H_(3)PO_(4) os tribasic acid and H_(3)PO_(4) is dibasic. Reason: In oxoacids only those H -atoms are replaceable which are attached to O-atom .

Statement: H_(3)PO_(3) is dibasic and H_(3)PO_(4) s tribasic acid. H_(3)PO_(3) and H_(3)PO_(4) on reacting with D_(2)O gives HD_(2) PO_(3) and D_(3)PO_(4) respectively.

STATEMENT-1 : In the given reaction, NaOH+H_(3)PO_(4)rarr NaH_(2)PO_(4)+H_(2)O equivalent mass of H_(3)PO_(4) is M//3 STATEMENT-2 : H_(3)PO_(4) is tribasic acid.

H_(3)PO_(3) is ..... acid

Among H_(3)PO_(4) and H_(3)PO_(3) - H_(3)PO_(3) is reducing agent and dibasic H_(3)PO_(4) is reducing agent and dibasic H_(3)PO_(4) is reducing agent and tribasic H_(3)PO_(3) is reducing agent and tribasic

Among H_(3)PO_(4) and H_(3)PO_(3) - H_(3)PO_(3) is reducing agent and dibasic H_(3)PO_(4) is reducing agent and dibasic H_(3)PO_(4) is reducing agent and tribasic H_(3)PO_(3) is reducing agent and tribasic

Explain why 'orthophosphoric acid, H_3 PO_4 , is tribasic but phosphorus acid, H_3 PO_3 , is dibasic'.