Which element from electron rich hydride ?

Options

A. C
B. O
C. B
D. Al

Answer

To determine which element forms an electron-rich hydride, we can follow these steps:

### Step 1: Understand the Classification of Hydrides
Hydrides can be classified into three categories based on their electron configuration:
1. **Electron Deficient Hydrides**: These are typically formed by elements in Group 13 (e.g., boron) and have incomplete octets.
2. **Electron Precise Hydrides**: These are formed by Group 14 elements (e.g., carbon) and have complete octets without extra electrons.
3. **Electron Rich Hydrides**: These are formed by elements in Groups 15, 16, and 17 (e.g., nitrogen, oxygen, and fluorine) and have complete octets along with non-bonding electrons (lone pairs).

### Step 2: Analyze the Given Options
The options provided are:
- A) Carbon
- B) Oxygen
- C) Boron
- D) Aluminum

### Step 3: Determine the Type of Hydride Formed by Each Element
- **Carbon (C)**: Forms electron precise hydrides (e.g., CH4).
- **Oxygen (O)**: Forms electron rich hydrides (e.g., H2O).
- **Boron (B)**: Forms electron deficient hydrides (e.g., BH3).
- **Aluminum (Al)**: Also forms electron deficient hydrides (e.g., AlH3).

### Step 4: Identify the Correct Answer
From the analysis:
- The only element among the options that forms electron-rich hydrides is **Oxygen (B)**.

### Final Answer
The element that forms electron-rich hydrides is **Oxygen** (Option B).

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