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Dimethyl glyoxime gives a red precipitat...

Dimethyl glyoxime gives a red precipitate with `Ni^(2+)`, which is used for its detection. To get this precipitate readily the best `pH` range is

A

`lt1`

B

`2-3`

C

`3-4`

D

`9-11`

Text Solution

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The correct Answer is:
To determine the best pH range for the precipitation of the red complex formed between dimethylglyoxime (DMG) and nickel(II) ions (Ni²⁺), we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Reaction**: Dimethylglyoxime (DMG) reacts with nickel(II) ions to form a red precipitate, which is a chelate complex. The formation of this complex is crucial for the detection of nickel ions. 2. **Identify the pH Influence**: The pH of the solution affects the solubility of the nickel-DMG complex. A specific pH range is required to ensure that the complex forms readily and does not dissolve back into the solution. 3. **Determine the Optimal pH Range**: It is known from chemical literature that the best pH range for the formation of the nickel-DMG complex is between pH 9 and pH 11. At this pH range, the reaction proceeds efficiently, leading to the formation of the red precipitate. 4. **Consider Buffering**: To maintain the pH within this optimal range, buffers such as ammonia or citrate are often used. These buffers help to stabilize the pH and prevent it from dropping below 5, which would favor the dissolution of the complex back into nickel ions. 5. **Evaluate the Options**: Given the options provided in the question, we can eliminate any ranges that are outside of the optimal pH range of 9 to 11. 6. **Conclusion**: The best pH range for the precipitation of the red complex with nickel(II) ions is from **pH 9 to pH 11**. ### Final Answer: The best pH range for the precipitation of the red complex with Ni²⁺ and dimethylglyoxime is **pH 9 to pH 11**.
To determine the best pH range for the precipitation of the red complex formed between dimethylglyoxime (DMG) and nickel(II) ions (Ni²⁺), we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Reaction**: Dimethylglyoxime (DMG) reacts with nickel(II) ions to form a red precipitate, which is a chelate complex. The formation of this complex is crucial for the detection of nickel ions. 2. **Identify the pH Influence**: The pH of the solution affects the solubility of the nickel-DMG complex. A specific pH range is required to ensure that the complex forms readily and does not dissolve back into the solution. ...
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