Atoms, Elements, Molecules, & Compounds

1 1 0 0 2 1 1 0 2 2 0 0 3 2 1 1 4 2 1 0 4 2 10 5 2 2 4 2 0 0 3 3 0 0 4 2 2 0 1 0 1 0 9 3 4 2 3 1 2 0 12 4 2 3 6 0 2 1 H2O O3 H2 CO2 CO NO2 CH4 c e b a d