NEET
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- NEET
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- Chemistry
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- Practical Chemistry
NEET · Chemistry · Practical Chemistry
Given below are two statements: one is labelled as Assertion (A)...
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Addition of dilute to a solid nitrite salt produces a reddish-brown gas.
Reason (R) : The reaction initially produces unstable nitrous acid () which decomposes to yield nitric oxide (), which is readily oxidised by air to form reddish-brown nitrogen dioxide ().
In the light of the above statements, choose the most appropriate answer from the options given below :
Assertion (A) : Addition of dilute to a solid nitrite salt produces a reddish-brown gas.
Reason (R) : The reaction initially produces unstable nitrous acid () which decomposes to yield nitric oxide (), which is readily oxidised by air to form reddish-brown nitrogen dioxide ().
In the light of the above statements, choose the most appropriate answer from the options given below :
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A)
- BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
- C(A) is true but (R) is false
- D(A) is false but (R) is true
Correct answer
A. Both (A) and (R) are true and (R) is the correct explanation of (A)
Step-by-step solution
Assertion (A) is true. When dilute is added to a nitrite () salt, a reddish-brown gas is evolved.
Reason (R) is also true and correctly explains (A). The reaction of nitrite with dilute acid produces nitrous acid (). Nitrous acid is unstable and disproportionates to give nitric acid, water, and nitric oxide ().
Nitric oxide () is a colourless gas, but it readily reacts with atmospheric oxygen to form nitrogen dioxide (), which is a reddish-brown gas.
Therefore, both (A) and (R) are true and (R) is the correct explanation of (A).
Answer: Both (A) and (R) are true and (R) is the correct explanation of (A)
Reason (R) is also true and correctly explains (A). The reaction of nitrite with dilute acid produces nitrous acid (). Nitrous acid is unstable and disproportionates to give nitric acid, water, and nitric oxide ().
Nitric oxide () is a colourless gas, but it readily reacts with atmospheric oxygen to form nitrogen dioxide (), which is a reddish-brown gas.
Therefore, both (A) and (R) are true and (R) is the correct explanation of (A).
Answer: Both (A) and (R) are true and (R) is the correct explanation of (A)