Match electrons answer help

carbon- 4

hydrogen- 1

magnesium- 2

oxygen- 6

hope it helps!

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

if you're asking what comes out, it's steam.