2 A 1.0 mol sample of He (9) at 25°C is mixed with a 1.0 mol sample of Xe (9) at 50'C. Which of the
following correctly predicts the changes in average kinetic energy and the aXekale speed of
the atoms that will occur as the mixture approaches thermal equilibrium?

hey your not cool]      

answer; i do believe the correct answer is (river); /// good luck

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.

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.