(A): `NO_(3)^(-)` ion is light bluish in colour.
(R): `NO_(3)^(-)`  ion is stabilised by resonance. 

Options

A. Both A & R are true, R is the correct explanation of A
B. Both A & R are true, R is not correct explanation of A
C. A is true, R is false
D. A is false, R is true

Answer

To analyze the given statements about the nitrate ion \((NO_3^−)\), we will follow these steps:

### Step 1: Evaluate the Assertion
The assertion states that the \((NO_3^−)\) ion is light bluish in color. However, the nitrate ion is actually known to be colorless or brown in solution. Therefore, this assertion is **false**.

### Step 2: Evaluate the Reason
The reason states that the \((NO_3^−)\) ion is stabilized by resonance. To understand this, we can draw the Lewis structure of the nitrate ion. The nitrate ion has one nitrogen atom bonded to three oxygen atoms. The structure can be represented as follows:

1. One nitrogen atom forms a double bond with one oxygen atom and single bonds with the other two oxygen atoms.
2. The negative charge is typically placed on one of the singly bonded oxygen atoms.

Next, we can draw the resonance structures:
- In one resonance structure, the double bond can be with the first oxygen, and the negative charge on the second oxygen.
- In another resonance structure, the double bond can be with the second oxygen, and the negative charge on the third oxygen.
- In the third resonance structure, the double bond can be with the third oxygen, and the negative charge on the first oxygen.

These resonance structures show that the negative charge is delocalized over the three oxygen atoms, which stabilizes the ion. Therefore, this reason is **true**.

### Step 3: Conclusion
Since the assertion is false and the reason is true, the correct relationship is that the assertion does not support the reason. Thus, the answer is that the assertion is false and the reason is true.

### Final Answer
(A) is false and (R) is true.

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