Question

define atomic number and mas number​

Answer 1

Answer:

The number of protons present in an atom is known as Atomic Number.

Sun of protons and neutrons present in the neucleus of an atom is called mass number.

Explanation:

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Answer 2

Answer:

Atomic number, the number of a chemical element in the periodic system, whereby the elements are arranged in order of increasing number of protons in the nucleus. Accordingly, the number of protons, which is always equal to the number of electrons in the neutral atom, is also the atomic number.

The mass number, also called atomic mass number or nucleon number, is the total number of protons and neutrons in an atomic nucleus. It is approximately equal to the atomic mass of the atom expressed in atomic mass units.

Explanation:

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