If atomic number 117,120 are discovered then their blocks will be

Options

A. s,p
B. p,s
C. p,d
D. d,p

Answer

To determine the blocks of elements with atomic numbers 117 and 120, we need to analyze their electronic configurations based on the periodic table and the order of filling of atomic orbitals.

### Step-by-Step Solution:

1. **Identify the Noble Gas Configuration**:
- The nearest noble gas before atomic numbers 117 and 120 is Radon (Rn), which has an atomic number of 86. The electronic configuration of Radon is:
\[ \text{Rn: } [Xe] 4f^{14} 5d^{10} 6s^{2} 6p^{6} \]

2. **Determine the Electronic Configuration for Atomic Number 117**:
- Atomic number 117 is one more than 116, which is the last filled element in the 7th period before 117. The electronic configuration can be built upon Radon:
\[ \text{For 117: } [Rn] 5f^{14} 6d^{10} 7s^{2} 7p^{5} \]
- Here, the last electron enters the 7p orbital, indicating that element 117 is a **p-block element**.

3. **Determine the Electronic Configuration for Atomic Number 120**:
- For atomic number 120, we continue from the configuration of 117:
\[ \text{For 120: } [Rn] 5f^{14} 6d^{10} 7s^{2} 7p^{6} 8s^{2} \]
- The last electron enters the 8s orbital, indicating that element 120 is an **s-block element**.

4. **Conclusion**:
- Therefore, atomic number 117 belongs to the **p-block**, and atomic number 120 belongs to the **s-block**.

### Final Answer:
- The blocks for atomic numbers 117 and 120 are **p-block** and **s-block**, respectively.