Help please giving brainliest

i think protons and neutrons

Explanation:

im not sure tho

Atomic mass is calculated by adding the masses of protons and neutrons in a given atom of an element.

Explanation:

For any given isotope, the sum of the numbers of protons and neutrons in the nucleus is called the mass number. This is because each proton and each neutron weigh one atomic mass unit (amu). By adding together the number of protons and neutrons and multiplying by 1 amu, you can calculate the mass of the atom.

Atomic mass is (just slightly less than) the sum of the masses of protons and neutrons in a given atom of an element.

hope this helps and is correct! :)

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

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