Balance this equation. if a coefficient of "1" is required, choose "blank" for that box. + o2 →
2
blank
4
3

2, Blank, 2 ;

The balanced chemical equation would be;

2 CO + O2 → 2 CO2

Balancing a chemical equation ensures that the number of atoms of each element are equal on both the reactants side and the products side. This ensures that the law of conservation of mass is obeyed in chemical reactions.

it's filtration, but this is an assumption so my apologies if i got this

i think that the answer is c