`NiCl_(2)+2dmg overset(NH_(4)OH)toNi(dmg)_(2)darr`

Options

A. For precipitate formation formation reaction
B. For precipitate dissolution reaction
C. For precipitate exchange reaction
D. For no reaction

Answer

To solve the question regarding the reaction of NiCl₂ with 2-dimethylglyoxime (dmg) in the presence of ammonium hydroxide (NH₄OH), we need to analyze the type of reaction taking place. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Reactants and Products
The reactants in the given equation are Nickel(II) chloride (NiCl₂) and dimethylglyoxime (dmg), while the product is Nickel(II) dimethylglyoxime complex (Ni(dmg)₂).

### Step 2: Understand the Reaction Type
In this reaction, we start with Nickel(II) chloride, which is soluble in water, and we introduce dimethylglyoxime in the presence of ammonium hydroxide. The reaction leads to the formation of a complex, which is typically insoluble in water.

### Step 3: Determine if a Precipitate is Formed
Since the product Ni(dmg)₂ is a complex that precipitates out of the solution, we can conclude that a solid (precipitate) is formed from the reactants, which were initially in solution.

### Step 4: Classify the Reaction
Given that we started with soluble reactants and ended up with an insoluble product (precipitate), this reaction can be classified as a precipitate formation reaction.

### Conclusion
Based on the analysis, the correct classification of the reaction is a **precipitate formation reaction**.