Which molecular formula corresponds to this model of a chemical compound? (black = carbon; red = oxygen; white = hydrogen) A ball-and-stick model has two black balls bonded to each other at center, with single-bonded red balls bonded to white balls above left and below right, and double-bonded red balls above right and below left. C2(OH)4 C2H2O4 C2H4O2 C4H2O2