Given below are the names of few elements based on their position in the periodic table. Identify the element which is not correctly placed.

Options

A. An element which tends to lose three electrons-Aluminium
B. An element which tends to gain two electrons-lodine
C. An element with valency four-Silicon
D. A transuranium element-plutonium

Explanation

To solve the question of identifying the incorrectly placed element based on their position in the periodic table, we will analyze each option step by step.

### Step 1: Analyze the first option - Aluminum
- **Statement**: An element which tends to lose three electrons is aluminum.
- **Atomic Number**: Aluminum has an atomic number of 13.
- **Electronic Configuration**: The electronic configuration of aluminum is 1s² 2s² 2p⁶ 3s² 3p¹.
- **Valence Electrons**: Aluminum has three valence electrons (3s² 3p¹).
- **Conclusion**: Aluminum can lose these three electrons to achieve a stable configuration (Al³⁺). This statement is **correct**.

### Step 2: Analyze the second option - Iodine
- **Statement**: An element which tends to gain two electrons is iodine.
- **Atomic Number**: Iodine has an atomic number of 53.
- **Electronic Configuration**: The electronic configuration of iodine is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 4p⁵.
- **Valence Electrons**: Iodine has seven valence electrons (4s² 4p⁵).
- **Conclusion**: Iodine needs only one more electron to complete its octet, not two. Therefore, this statement is **incorrect**.

### Step 3: Analyze the third option - Silicon
- **Statement**: An element with valency 4 is silicon.
- **Atomic Number**: Silicon has an atomic number of 14.
- **Electronic Configuration**: The electronic configuration of silicon is 1s² 2s² 2p⁶ 3s² 3p².
- **Valence Electrons**: Silicon has four valence electrons (3s² 3p²).
- **Conclusion**: Silicon can form covalent bonds by sharing four electrons, making this statement **correct**.

### Step 4: Analyze the fourth option - Plutonium
- **Statement**: A transuranium element is plutonium.
- **Atomic Number**: Plutonium has an atomic number of 94.
- **Definition**: Transuranium elements are those that have atomic numbers greater than 92 (the atomic number of uranium).
- **Conclusion**: Since plutonium is indeed after uranium in the periodic table, this statement is **correct**.

### Final Conclusion
After analyzing all the options, the element that is not correctly placed is **Iodine**, as it tends to gain only one electron, not two.

### Summary of the Answer
The incorrectly placed element is **Iodine**.

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