Atoms release energy when_
a. electrons move to a lower energy level
b. electrons move to a higher energy level
c. protons move to a higher energy level
d. protons move to a lower energy level

A. Electrons move to a lower energy level (gradpoint)

Explanation:

When electrons jump down to a lower energy level, they release energy. Atoms may emit this energy in the form of light.

i dont know the answe

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.