N(9) + 3H2(9) 2NH3 (9) Which statement is true for the equilibrium system?
The concentration of NH, is greater than the concentration of N2.
O The concentration of NH3 equals the concentration of N2.
The rate of the forward reaction equals the rate of the reverse reaction.
O The rate of the forwald reaction is greater than the rate of the reverse reaction.

the awnser is group 12

you need to have a picture of the atom that way we can answer it

b.false that your answer

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.