Magnesium is a highly flammable element which is easily combustible in the presence of oxygen: 2mg + o2 --> ? ? + heat how many atoms would you expect to find on the product side of this equation?

The  number of atoms  would expect to find  on the product side of the reaction between Mg and O₂  is  4  atoms

Explanation

Mg  react  with O₂  to produce MgO  according   to  reaction below

2Mg  +O₂ →2 MgO   +heat

MgO is the product ,therefore  the  number of atoms  in product  side is

= 2 [ atoms  of Mg + atoms  of O]

= 2[ 1+1]  = 4 atoms

it means there are 3 atoms of oxygen