Question

Assertion: In ${{P}_{4}}$, the valency and oxidation number of phosphorus are the same.
Reason: In the reaction between phosphorus and sodium hydroxide, the phosphorus acts as both oxidizing and reducing agents.
A.Both assertion and reason are correct and reason is the correct explanation for assertion.
B.Both assertion and reason are correct and the reason is not the correct explanation for assertion.
C.The assertion is correct but the reason is incorrect.
D.Both assertion and reason are incorrect.

Answer 1

Before answering this question, we should know the oxidation number. The number that shows the total number of electrons lost or gained by it is known as the oxidation number. The oxidation state means the same, it is another name for oxidation number

Complete answer:
Phosphorus is present in the food in the form of phosphate and phosphate esters. Passive absorption in the small intestine is faced by phosphorus, some get absorbed by active transport as well. Phosphorus helps to regulate gene transcription, helps to maintain the pH in energy storage. It also activates the enzymes. Phosphorus forms 1-1.5% fat-free mass. Our bones and teeth comprise 85 % and 15% are there all over the blood and soft tissues.
The oxidation number of phosphorus in ${{P}_{4}}$is zero whereas the valency of phosphorus in ${{P}_{4}}$is three as each P atom is attached to three other P atoms.
The reaction between phosphorus and nitrogen brings a change in the oxidation state of phosphorus from 0 to +3 and +1. The oxidation state of other atoms is the same.
The reaction which phosphorus undergoes is-
${{P}_{4}}+3NaOH+3{{H}_{2}}O\to 3Na{{H}_{2}}P{{O}_{2}}+P{{H}_{3}}$

So, Option (D) is correct- Both assertion and reason are incorrect.

Note:
Phosphorous is a vital mineral that is present organically in many foods and is taken as a dietary supplement too. Our bones, teeth, DNA, and RNA comprises phosphorus. Our cell membrane also has phosphorus in the form of phospholipids. It is a component in RNA as well.