The element with atomic number 118 is likely to have the same outer shell configuration as an element with atomic number

Options

A. 18
B. 28
C. 58
D. 88

Answer

To determine which element has the same outer shell configuration as the element with atomic number 118, we can follow these steps:

### Step 1: Identify the electronic configuration of element 118
- The element with atomic number 118 is Oganesson (Og). Its electronic configuration can be derived from the preceding noble gas, Radon (Rn), which has an atomic number of 86.
- The electronic configuration of Radon is:
\[ [Rn] = 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 \]
- For element 118, the configuration becomes:
\[ [Rn] 5f^{14} 6d^{10} 7s^2 7p^6 \]

### Step 2: Determine the outer shell configuration
- The outer shell configuration of Oganesson (element 118) is:
\[ 7s^2 7p^6 \]
- This configuration indicates that it has a complete outer shell, characteristic of noble gases.

### Step 3: Check the configurations of the given atomic numbers
- We need to check the electronic configurations of the elements with atomic numbers 18, 28, 58, and 88 to find which one has the same outer shell configuration.

1. **Atomic Number 18 (Argon)**:
- Configuration:
\[ 1s^2 2s^2 2p^6 3s^2 3p^6 \]
- Outer shell: \(3s^2 3p^6\) (noble gas configuration)

2. **Atomic Number 28 (Nickel)**:
- Configuration:
\[ 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8 \]
- Outer shell: \(4s^2 3d^8\) (not a noble gas configuration)

3. **Atomic Number 58 (Cerium)**:
- Configuration:
\[ [Xe] 6s^2 4f^1 \]
- Outer shell: \(6s^2 4f^1\) (not a noble gas configuration)

4. **Atomic Number 88 (Radium)**:
- Configuration:
\[ [Rn] 7s^2 \]
- Outer shell: \(7s^2\) (not a noble gas configuration)

### Step 4: Conclusion
- The only element among the options that has a noble gas outer shell configuration similar to Oganesson (element 118) is Argon (element 18).
- Therefore, the element with atomic number 118 is likely to have the same outer shell configuration as the element with atomic number **18**.

### Final Answer:
The element with atomic number 118 is likely to have the same outer shell configuration as an element with atomic number **18**.

---