Which statement explains why a covalent bond between two different atoms is polar?
A. One atom has gained one or more electrons and the other has lost one or more electrons.

B. The electrons are attracted to the atom which has the greatest atomic mass resulting in an unequal distribution of charge.

C. The bonding pair of electrons are attracted more strongly to the atom with the less negative value of electron affinity resulting in an unequal distribution of charge.

D. The bonding pair of electrons are attracted more strongly towards the more electronegative atom resulting in an unequal distribution of charge.

D. The bonding pair of electrons are attracted more strongly towards the more electronegative atom resulting in an unequal distribution of charge.

Explanation:

In a polar covalent bond, the electrons are not equally shared because one atom spends more time with the electrons than the other atom.

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.