Salt `A+SrarrBoverset(BaCl_(2))rarr` White precipitate A is paramagnetic in nature and contains about 55% K. Thus, A is

Options

A. `K_(2)O`
B. `K_(2)O_(2)`
C. `KO_(2)`
D. `K_(2)SO_(4)`

Answer

To solve the question regarding the salt A, we need to analyze the given information step by step.

### Step 1: Understand the Composition of Salt A
We know that salt A is a compound that contains about 55% potassium (K). This percentage indicates that the compound is likely to be a potassium salt.

**Hint:** Look for compounds that contain potassium and calculate their percentage composition.

### Step 2: Identify the Nature of Salt A
The problem states that salt A is paramagnetic. Paramagnetic substances have unpaired electrons, which is a characteristic of certain compounds, especially those containing transition metals or specific anions.

**Hint:** Recall that paramagnetic substances have unpaired electrons. Check the electronic configuration of potential candidates.

### Step 3: Consider Possible Compounds
Given that A contains potassium and is paramagnetic, we should consider potassium compounds. The options might include various potassium oxides or superoxides.

**Hint:** Focus on oxides or superoxides of potassium, as they are common compounds that could fit the description.

### Step 4: Calculate the Weight Percentage of Potassium
To confirm the identity of salt A, we can calculate the weight percentage of potassium in some potential candidates.

For example, consider potassium superoxide (KO2):
- Molar mass of K = 39 g/mol
- Molar mass of O2 = 32 g/mol
- Molar mass of KO2 = 39 + 32 = 71 g/mol

Now, calculate the weight percentage of potassium:
\[ \text{Weight \% of K} = \left( \frac{39}{71} \right) \times 100 \approx 54.93\% \]

This is approximately 55%, which matches the given information.

**Hint:** Perform similar calculations for other potassium compounds to confirm if they meet the criteria.

### Step 5: Confirm the Paramagnetic Nature
Potassium superoxide (KO2) is known to be paramagnetic due to the presence of unpaired electrons in the superoxide ion (O2^-). This confirms that the compound is indeed paramagnetic.

**Hint:** Verify the electronic structure of the compound to ensure it has unpaired electrons.

### Conclusion
Based on the analysis, we conclude that salt A is potassium superoxide (KO2), which is a white precipitate, paramagnetic in nature, and contains approximately 55% potassium.

**Final Answer:** Salt A is KO2 (potassium superoxide).

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