Which of the following is true about cos.1.cos has no dipole moment because the molecule is linear and dipole moments cancel in linear molecules.2.cos has a dipole moment because it is asymmetric and the dipole moments do not completely cancel.3.cos has a dipole moment because the molecule is bent and the dipole moments combine.4.cos has no dipole moment because it is bent and the dipole moments cancel5.cos has no dipole moment because its bonds are all non polar.

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.