Question

The atom of an element has 4 protons 5 neutrons and 4 electrons what is the atomic mass of the number of this atom

Answer 1

A neutral atom will have the same number of electrons is does protons. Since it has 4 protons, it must have an atomic number of 4. (That makes itberyllium.) Since it has a 4 protons and 5 neutrons, it has a mass number of 9.

Answer 2

THE ATOMIC MASS WILL BE 9 amu.

Explanation:

• Protons, neutrons, electrons are represented by $p^{+},n,e^{-}$.
• The atomic mass is the sum of  $p^{+}$ and  $n$.
• In an atom no. of  $p^{+}$  and  $e^{-}$  are equal.
• The mass of an atom is confined in a small part that is the nucleus. Protons, neutrons are present in it.
• The element has 4  $p^{+}$ and 5  $n$ so, atomic mass will be

         $p^{+}+n=4+5=9amu$.

• The element given is beryllium ($^{9}_{4} Be$).