Question

An atom has three shells. If there are four electrons in the third shell then What is its atomic number? and what is number of electrons??​

Answer 1

Explanation:

atomic no. - 14(Silicon)

Answer 2

Understanding the question:

• First shell and Second shell are completely filled.
• The Third shell contains 4 electrons.

We need to find:

1. Atomic number
2. Number of Valence electrons

Solution

First shell or K shell can hold only 2 Electrons.

Second shell or L shell can hold upto 8 electrons.

Third shell or M shell also can hold upto 8 electrons.

The atomic structure of the given compound is in attachment.

So, the total number of electrons in the compound is

2 + 8 + 4 = 14 Electrons

The given element is Silicon

Valence electrons are the empty electrons present in the outermost shell.

Here, Valence electrons = 4

Atomic number = Number of electrons = 14