Quidei Learns

Atomic Number (Z)

Atomic number is the number of protons present in the nucleus of an atom. It is represented by the symbol Z. Every element has a unique atomic number, which identifies the element. In a neutral atom, the number of electrons is equal to the atomic number.

Key Points:

* Symbol: Z
* Equals the number of protons in the nucleus.
* Determines the identity of an element.
* In a neutral atom: Number of protons = Number of electrons.
* Elements are arranged in the periodic table according to increasing atomic number.

Example:

* Hydrogen (H): Atomic Number = 1 (1 proton)
* Carbon (C): Atomic Number = 6 (6 protons)
* Oxygen (O): Atomic Number = 8 (8 protons)
* Sodium (Na): Atomic Number = 11 (11 protons)