In the periodic table, the element with atomic number 12 will be placed in the group

Options

A. First
B. Fourth
C. Fifteenth
D. Second

Answer

To determine the group of the element with atomic number 12 in the periodic table, we can follow these steps:

### Step 1: Identify the Element
The atomic number 12 corresponds to the element Magnesium (Mg).

### Step 2: Determine the Electronic Configuration
To find the electronic configuration of Magnesium, we fill the orbitals according to the Aufbau principle:
- The first shell can hold 2 electrons: 1s²
- The second shell can hold 8 electrons: 2s² 2p⁶
- The third shell can hold 2 electrons: 3s²

Thus, the complete electronic configuration of Magnesium is:
1s² 2s² 2p⁶ 3s²

### Step 3: Identify the Valence Electrons
The valence electrons are the electrons in the outermost shell. For Magnesium, the outermost shell is the third shell (3s), which contains 2 electrons (3s²).

### Step 4: Determine the Group Number
In the periodic table, the group number for s-block elements is equal to the number of valence electrons. Since Magnesium has 2 valence electrons, it belongs to Group 2.

### Conclusion
Therefore, the element with atomic number 12 (Magnesium) is placed in Group 2 of the periodic table.

### Final Answer
The correct option is D: 2nd.

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