Answer the question on the basis of the passage given below:
Oxides formed by \(p\)- block elements are acidic, basic and neutral. Also, elements of \(p\)-block from different acids.
Match List I with List II
| List I | List II |
| A. \(H_4P_2O_7\) | I. +1 |
| B. \(H_4P_2O_6\) | II. +3 |
| C. \(H_3PO_2\) | III. +4 |
| D. \(H_3PO_3\) | IV. +5 |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is option 2. A-IV, B-III, C-I, D-II.
| List I | List II |
| A. \(H_4P_2O_7\) | IV. +5 |
| B. \(H_4P_2O_6\) | III. +4 |
| C. \(H_3PO_2\) | I. +1 |
| D. \(H_3PO_3\) | II. +3 |
A. \(H_4P_2O_7\) : IV. +5:
The compound \(H_4P_2O_7\) is known as pyrophosphoric acid.
Let the oxidation number of \(P\) in \(H_4P_2O_7\) be \(x\). Then,
\(4 × (+1) + 2x + 7 × (-2) = 0\)
or, \(4 + 2x - 14 = 0\)
or, \(2x - 10 = 0\)
or, \(x = +5\)
B. \(H_4P_2O_6\) : III. +4:
The compound \(H_4P_2O_6\) is known as hypophosphoric acid.
Let the oxidation number of \(P\) in \(H_4P_2O_6\) be \(x\). Then,
\(4 × (+1) + 2x + 6 × (-2) = 0\)
or, \(4 + 2x - 12 = 0\)
or, \(2x - 8 = 0\)
or, \(x = +4\)
C. \(H_3PO_2\) : I. +1:
The compound \(H_4P_2O_7\) is known as hypophosphorous acid.
Let the oxidation number of \(P\) in \(H_3PO_2\) be \(x\). Then,
\(3 × (+1) + x + 2 × (-2) = 0\)
or, \(3 + x - 4 = 0\)
or, \(x - 1= 0\)
or, \(x = +1\)
D. \(H_3PO_3\) : II. +3:
The compound \(H_4P_2O_7\) is known as phosphorous acid.
Let the oxidation number of \(P\) in \(H_3PO_3\) be \(x\). Then,
\(3 × (+1) + x + 3 × (-2) = 0\)
or, \(3 + x - 6 = 0\)
or, \(x - 3= 0\)
or, \(x = +3\)
