An electron in an isolataed atom, may be described by four quantum number n,l,m and s. The value of m for electron most easily removed from a gaseous atom of n-alkaline earth metal is

Options

A. same as the maximum value of n for the element
B. any number from `-(n-1)` to `+(n-1)`
C. an positive number from 1 to (n-1)
D. zero

Answer

To solve the question regarding the value of the magnetic quantum number (m) for the electron most easily removed from a gaseous atom of an alkaline earth metal, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Group of Elements**:
Alkaline earth metals belong to Group 2 of the periodic table. The elements in this group include Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra).

**Hint**: Remember that alkaline earth metals are in Group 2 and have similar electronic configurations.

2. **Determine the General Electronic Configuration**:
The general electronic configuration for alkaline earth metals is \( ns^2 \), where \( n \) is the principal quantum number that corresponds to the outermost shell.

**Hint**: The outermost electrons are the valence electrons, which are crucial for determining the properties of the element.

3. **Identify the Valence Electrons**:
Each alkaline earth metal has two valence electrons in the outermost s orbital. For example:
- Beryllium: \( 1s^2 2s^2 \)
- Magnesium: \( 1s^2 2s^2 2p^6 3s^2 \)

**Hint**: Focus on the outermost shell where the valence electrons reside.

4. **Understand the Quantum Numbers**:
Each electron in an atom is described by four quantum numbers:
- Principal quantum number (n)
- Azimuthal quantum number (l)
- Magnetic quantum number (m)
- Spin quantum number (s)

5. **Determine the Values of Quantum Numbers for the Valence Electrons**:
- For the s orbital, the azimuthal quantum number \( l \) is 0.
- The magnetic quantum number \( m \) for an s orbital can only take the value of 0 (since \( m \) can range from \(-l\) to \(+l\)).

**Hint**: Recall that the s orbital has only one orientation in space, which corresponds to \( m = 0 \).

6. **Conclusion**:
Since the most easily removed electron from an alkaline earth metal is one of the valence electrons in the s orbital, the magnetic quantum number \( m \) for this electron is 0.

**Final Answer**: The value of \( m \) for the electron most easily removed from a gaseous atom of an alkaline earth metal is \( 0 \).