how many valence electrons?

Explanation:

Step1: Identify the element

The element is carbon (C), which has an atomic number of 6.

Step2: Determine electron - shell configuration

The electron - shell configuration of carbon is 2, 4. The first shell can hold 2 electrons and the second shell holds the remaining electrons.

Step3: Define valence electrons

Valence electrons are the electrons in the outermost shell. For carbon, the outermost shell has 4 electrons.

Answer:

4