Which of the following is//are true for oxygen.

Options

A. `KMnO_(4)`(s) on strong heating gives oxygen gas
B. Oxygen mixed with helium is used for artificial respiration.
C. It has two unparied electrons in bonding `pi` molecular orbitals.
D. Brins process is used as industrial method for the preparation of oxygen gas.

Explanation

To determine which statements about oxygen are true, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement:** KMnO4 on strong heating gives oxygen gas.

**Solution:**
When potassium permanganate (KMnO4) is heated strongly, it decomposes to form potassium manganate (K2MnO4), manganese dioxide (MnO2), and oxygen gas (O2). The reaction can be represented as:
\[ 2 KMnO_4 \rightarrow K_2MnO_4 + MnO_2 + O_2 \]
Thus, this statement is **true**.

### Step 2: Analyze the second statement
**Statement:** Oxygen mixed with helium is used for artificial respiration.

**Solution:**
A mixture of oxygen and helium, known as Heliox, is indeed used in artificial respiration. Helium is less soluble in blood, which helps improve the efficiency of oxygen delivery in certain medical situations. Therefore, this statement is also **true**.

### Step 3: Analyze the third statement
**Statement:** It has two unpaired electrons in bonding pi molecular orbital.

**Solution:**
To analyze this, we need to look at the molecular orbital configuration of O2. The electronic configuration is:
- 1s², σ*1s², σ2s², σ*2s², σ2p², π2p² (x), π2p² (y), π*2p¹ (x), π*2p¹ (y).

In the O2 molecule, there are 16 electrons total. The two unpaired electrons are actually in the antibonding π* orbitals, not in the bonding π orbitals. Therefore, this statement is **false**.

### Step 4: Analyze the fourth statement
**Statement:** Brin's process is used as an industrial method for the preparation of oxygen gas.

**Solution:**
Brin's process involves the reaction of barium oxide (BaO) with air at high temperatures, leading to the formation of barium peroxide (BaO2), which can decompose to release oxygen gas. The overall reaction can be summarized as:
\[ BaO + O_2 \rightarrow BaO_2 \quad \text{and} \quad BaO_2 \rightarrow BaO + O_2 \]
Thus, this statement is **true**.

### Final Conclusion:
The true statements regarding oxygen are:
1. KMnO4 on strong heating gives oxygen gas. (True)
2. Oxygen mixed with helium is used for artificial respiration. (True)
3. It has two unpaired electrons in bonding pi molecular orbital. (False)
4. Brin's process is used as an industrial method for the preparation of oxygen gas. (True)

### Summary of True Statements:
- Statements 1, 2, and 4 are true.
- Statement 3 is false.

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