Question

Explain with examples

Atomic number

Answer 1

Atomic Number ($\mathrm{z}$):

• The atomic number of an atom is the total number of protons in its nucleus.
• All atoms of the element have the same number of protons, and hence the same atomic number.
• The atomic numbers of different elements are different.
• The atomic number of an atom can be represented by “$\mathrm{z}$”

Example:

• The nucleus of all Carbon atoms has 6 protons, so the atomic number is 6 for all Carbon atoms.
• The nucleus of all Oxygen atoms has eight protons so the atomic number is 8 for all Oxygen atoms.

Therefore, atomic number is the number of protons that are present in the atom of an element.