The number of electrons in the valence shell of calcium is

Options

A. 6
B. 8
C. 2
D. 4

Answer

To determine the number of electrons in the valence shell of calcium, we can follow these steps:

### Step 1: Identify the Atomic Number of Calcium
Calcium has an atomic number of 20. This means it has 20 electrons.

### Step 2: Write the Electronic Configuration
The electronic configuration of calcium can be written as follows:
- 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

### Step 3: Determine the Valence Shell
The valence shell is the outermost shell of an atom that contains electrons. For calcium, the outermost shell is the 4th shell (n=4).

### Step 4: Count the Electrons in the Valence Shell
From the electronic configuration, we can see that the electrons in the 4th shell (4s²) are:
- 4s² = 2 electrons

### Conclusion
Therefore, the number of electrons in the valence shell of calcium is **2**.

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