The atomic number of an element is 11 and its mass number is 23. The respective number of elec­ trons, protons and neutrons in this atom will be

Options

A. 11, 11, 12
B. 11,12, 11
C. 12, 11, 11
D. 23, 11,23

Answer

To solve the question regarding the atomic number and mass number of an element, we need to determine the number of electrons, protons, and neutrons in the atom. Here’s how to approach it step by step:

### Step-by-Step Solution:

1. **Identify the Atomic Number (Z)**:
- The atomic number of the element is given as 11.
- The atomic number represents the number of protons in the nucleus of the atom.

**Hint**: Remember that the atomic number is always equal to the number of protons in a neutral atom.

2. **Determine the Number of Protons**:
- Since the atomic number (Z) is 11, the number of protons (P) is also 11.

**Hint**: The number of protons is equal to the atomic number.

3. **Identify the Mass Number (A)**:
- The mass number of the element is given as 23.
- The mass number is the total number of protons and neutrons in the nucleus.

**Hint**: The mass number is the sum of protons and neutrons.

4. **Calculate the Number of Neutrons (N)**:
- We can find the number of neutrons using the formula:
\[ \text{Neutrons} (N) = \text{Mass Number} (A) - \text{Atomic Number} (Z) \]
- Substituting the values:
\[ N = 23 - 11 = 12 \]

**Hint**: Neutrons can be calculated by subtracting the number of protons from the mass number.

5. **Determine the Number of Electrons**:
- In a neutral atom, the number of electrons (E) is equal to the number of protons. Therefore, since we have 11 protons, we also have 11 electrons.

**Hint**: In a neutral atom, the number of electrons equals the number of protons.

6. **Summarize the Results**:
- Number of Electrons = 11
- Number of Protons = 11
- Number of Neutrons = 12

7. **Final Answer**:
- The respective numbers of electrons, protons, and neutrons in this atom are 11, 11, and 12.

### Conclusion:
The correct sequence of the number of electrons, protons, and neutrons is **11, 11, 12**.