A non-metal M forms `MCl_(3),M_(2)O_(5) and Mg_(3)M_(2)` but does not form `MI_(5)`, then incorrect statement regarding non-metal M is

Options

A. M can form mutiple bond
B. M is of second period element
C. Atomicity of non-metal is 4
D. The range of oxidation number for M is -3 to +5

Explanation

To solve the question, we need to analyze the properties of the non-metal M based on the compounds it forms and the information given.

### Step-by-Step Solution:

1. **Identify the Compounds and Their Formulas**:
- The non-metal M forms the following compounds:
- \( MCl_3 \)
- \( M_2O_5 \)
- \( Mg_3M_2 \)
- It does not form \( MI_5 \).

2. **Determine the Oxidation States**:
- For \( MCl_3 \):
- Let the oxidation state of M be \( x \).
- The equation is: \( x + 3(-1) = 0 \) (since Cl has a -1 charge).
- Solving gives: \( x = +3 \).

- For \( M_2O_5 \):
- Let the oxidation state of M be \( x \).
- The equation is: \( 2x + 5(-2) = 0 \) (since O has a -2 charge).
- Solving gives: \( 2x - 10 = 0 \) → \( x = +5 \).

- For \( Mg_3M_2 \):
- Let the oxidation state of M be \( x \).
- The equation is: \( 3(+2) + 2x = 0 \) (since Mg has a +2 charge).
- Solving gives: \( 6 + 2x = 0 \) → \( 2x = -6 \) → \( x = -3 \).

3. **Summary of Oxidation States**:
- The oxidation states of M are \( +3, +5, \) and \( -3 \).
- This indicates that M can exhibit a range of oxidation states from \( -3 \) to \( +5 \).

4. **Analyze the Non-Metal M**:
- Since M forms \( MCl_3 \) and \( M_2O_5 \), it is likely a non-metal that can form multiple bonds.
- The fact that it does not form \( MI_5 \) suggests that it cannot expand its valence shell to accommodate five bonds, indicating that M is likely a second-period element (like nitrogen) which lacks d-orbitals.

5. **Identify the Incorrect Statement**:
- The options provided likely include statements about M's ability to form multiple bonds, its atomicity, its period, and its oxidation states.
- Since we established that M is likely nitrogen, we know:
- Nitrogen can form multiple bonds (correct).
- Nitrogen is a second-period element (correct).
- The atomicity of nitrogen is 2 (incorrect statement if it states atomicity is 4).
- The oxidation states range from -3 to +5 (correct).

6. **Conclusion**:
- The incorrect statement regarding non-metal M is that "the atomicity of non-metal is 4". The correct atomicity of nitrogen is 2.

### Final Answer:
The incorrect statement regarding non-metal M is that "the atomicity of non-metal is 4".