Question

is it necessary that the atomic mass is always twice the atomic number ?

Answer 1

no dear there is no rule that the atomic mass is always twice the atomic number.it is there only for some elements .

Answer 2

Hey friend,
No, it's not necessary that the atomic mass of any element is always double of the atomic number.
The atomic mass equals = no. of protons + no. Of neutrons.

For example : Argon have atomic number = 18 and atomic mass = 40

Hope this helps!!!

@Mahak24

Thanks...
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