nguyên tử A có tổng hợp số hạt nơtron, electron, proton là 21 trong đó số hạt không mang điện bằng số hạt mang điện. tìm số hạt mỗi loại

c. is the answer

by love gaming

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.