Reaction Mechanism

∴ In final solution 2 millimoles of NH₄Cl is present.

The correct answer is (A) : 

- The Mond process is used for refining nickel. In this process, impure nickel reacts with carbon monoxide at moderate temperatures to form volatile nickel tetracarbonyl .
The reaction is:

- The volatile is then decomposed at high temperatures to obtain pure nickel.
Final Answer: (1) .

- In the reaction involving an electron-donating group like , the electron density on the benzene ring is increased, leading to a faster nucleophilic attack. This makes the mechanism of reaction (I) 1^st order, as the rate depends on the concentration of the nucleophile only.

In the reaction involving an electron-withdrawing group like , the electron density on the benzene ring is decreased, which slows down the nucleophilic substitution and typically follows a 2^ndorder mechanism, where both the nucleophile and the substrate are involved in the rate-determining step. However, reaction (II) involves a 1^st order mechanism because the presence of only partially influences the overall rate, which results in an overall first-order reaction. 
Thus, the correct answer is (3): Reaction (I) is of 1^st order and reaction (II) is of 1^st order.

The reaction proceeds as follows:
1. reacts with the carbonyl group to form a cyanohydrin ( and groups on the same carbon).
2. Ethanol in the presence of hydrolyzes the cyanohydrin to form a carboxylic acid group ( ) and retains the hydroxyl group.
Thus, the major products are as shown in option (4), where the carboxylic acid ( ) and hydroxyl ( ) groups are appropriately positioned.

1.Ostwald Process: In the Ostwald process, ammonia ( ) is oxidized by air to form nitric oxide ( ):

Thus, “A” is NO.
2. Further Oxidation of NO: Nitric oxide ( ) reacts with oxygen to form nitrogen dioxide ( ):

Thus, “B” is NO .
3. Hydration of NO : Nitrogen dioxide ( ) reacts with water to form nitric acid ( ) and nitric oxide ( ):

4. Properties of HNO : Nitric acid is an oxoacid of nitrogen. It gives a positive brown ring test, confirming the presence of NO.
Final Answer: .

1. Analysis of the Graph:
- In region-I, the rate of reaction increases linearly with the concentration, which is characteristic of a first-order reaction.
- In region-II, the graph shows non-linear behavior, indicating that the reaction order is fractional (in the range of 0.1 to 0.9).
- In region-III, the rate becomes constant, indicating a zero-order reaction.
2. Verification of Statements:
- (A) Incorrect. The overall order cannot be determined directly from the graph as it changes across regions.
- (B) Incorrect. The order can be inferred for specific regions.
- (C) Correct. Region-I corresponds to first-order behavior, and region-III corresponds to zero-order behavior.
- (D) Incorrect. In region-II, the reaction is not of first order.
- (E) Correct. In region-II, the reaction order lies between 0.1 and 0.9.
3. Conclusion:
- The correct statements are (C) and (E).

1. Retardation Factor ( ):
The value is defined as:

2. Given Data:
Total length of the TLC plate = 6 cm.
Let the solute travel 3.6 cm and the solvent front travel 6 cm.
3. Calculate :

4.Convert to Factor:

Final Answer: .