Name an element which has a total of two shells and there are three electrons in its valence shell.

Explanation

To solve the question, we need to identify an element that has a total of two electron shells and three electrons in its valence shell. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Concept of Electron Shells
- An element with two shells means it has electrons in the first and second energy levels (n=1 and n=2).
- The first shell (n=1) can hold a maximum of 2 electrons, while the second shell (n=2) can hold up to 8 electrons.

**Hint:** Remember that the maximum number of electrons in a shell is given by the formula 2n², where n is the shell number.

...