An element X belongs to fourth period and fifteen group of the periodic table . Which of the following statements is true ?

Options

A. It has a completely filled s- orbital and a partially filled d- orbital
B. It has completely filled s- orbital and a partially filled d- orbital
C. It has completely filled s- and p- orbitals and a half filled d- orbital
D. It has a half filled p- orbital and completely filled s- and d- orbitals .

Explanation

To determine which statement is true for the element X that belongs to the fourth period and the fifteenth group of the periodic table, we first need to identify the element and its electronic configuration.

### Step-by-Step Solution:

1. **Identify the Element:**
- The element X is in the fourth period and the fifteenth group of the periodic table.
- The elements in group 15 are Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb), and Bismuth (Bi).
- In the fourth period, the element in group 15 is Arsenic (As).

2. **Determine the Atomic Number:**
- Arsenic (As) has an atomic number of 33.

3. **Write the Electronic Configuration:**
- The electronic configuration of Arsenic can be derived from the atomic number.
- The configuration is:
- 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p³
- This can be simplified using the noble gas configuration:
- [Ar] 4s² 3d¹⁰ 4p³

4. **Analyze the Orbitals:**
- In the electronic configuration:
- The 4s orbital is completely filled with 2 electrons.
- The 3d orbital is completely filled with 10 electrons.
- The 4p orbital has 3 electrons, which means it is half-filled (since it can hold a maximum of 6 electrons).

5. **Evaluate the Statements:**
- Now, we need to evaluate the given statements about the electronic configuration:
1. **Statement 1:** It has completely filled S orbital and partially filled D orbital.
- **False** (D orbital is completely filled).
2. **Statement 2:** It has completely filled S and P orbital.
- **False** (P orbital is half-filled).
3. **Statement 3:** It has half filled P orbital and completely filled S and D orbital.
- **True** (S and D orbitals are completely filled, P orbital is half-filled).
4. **Statement 4:** It has completely filled S and P orbital.
- **False** (P orbital is half-filled).

6. **Conclusion:**
- The true statement is: "It has half filled P orbital and completely filled S and D orbital."

### Final Answer:
The correct statement is: "It has half filled P orbital and completely filled S and D orbital."

---