The following are some statements related to VA group hydrides
I) Reducing property increases from `NH_(3)` to `BiH_(3)`
II) Tendency to donate lone pair decreases from `NH_(3)` to `BiH_(3)`
III) Ease of replacing H with `Cl` decreases from `NH_(3)` to `BiH_(3)`
IV) Ease of formation of hydrides decreases from `NH_(3)` to `BiH_(3)`
The correct statement are

Options

A. I,II,III and IV
B. I,III and IV
C. I,II and IV
D. I and IV

Explanation

To solve the question regarding the statements related to VA group hydrides, we will analyze each statement one by one.

### Step 1: Analyze Statement I
**Statement I:** Reducing property increases from `NH3` to `BiH3`.

- **Explanation:** As we move down the group from nitrogen (NH3) to bismuth (BiH3), the atomic size increases. This increase in atomic size leads to a longer bond length and weaker bond strength for the M-H bonds (where M is the group VA element). Therefore, it becomes easier for the hydrides to act as reducing agents because the bonds can break more easily. Thus, the reducing property does indeed increase from `NH3` to `BiH3`.

**Conclusion:** Statement I is correct.

### Step 2: Analyze Statement II
**Statement II:** Tendency to donate lone pair decreases from `NH3` to `BiH3`.

- **Explanation:** Ammonia (NH3) is a strong base and has a high tendency to donate its lone pair of electrons. As we move down the group to bismuthine (BiH3), the basicity decreases due to the increasing size of the central atom, which stabilizes the lone pair more effectively. Therefore, the tendency to donate the lone pair decreases down the group.

**Conclusion:** Statement II is correct.

### Step 3: Analyze Statement III
**Statement III:** Ease of replacing H with Cl decreases from `NH3` to `BiH3`.

- **Explanation:** The ease of replacing hydrogen with chlorine is related to the basicity of the hydrides. Since NH3 is more basic than BiH3, it can more readily react with chlorine to form NH2Cl compared to BiH3. Thus, the ease of replacing H with Cl does indeed decrease from `NH3` to `BiH3`.

**Conclusion:** Statement III is correct.

### Step 4: Analyze Statement IV
**Statement IV:** Ease of formation of hydrides decreases from `NH3` to `BiH3`.

- **Explanation:** The formation of hydrides is influenced by the stability of the hydride formed. NH3 is a stable compound and forms easily, while BiH3 is less stable due to the larger size of bismuth and the weaker M-H bond. Therefore, the ease of formation of hydrides does decrease from `NH3` to `BiH3`.

**Conclusion:** Statement IV is correct.

### Final Conclusion
All four statements are correct. Therefore, the correct answer is that all statements I, II, III, and IV are true.

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