Hello. I would like to chime in about this problem. When you divide this spatial problem into vertical sections, you lose the connection between the cancelled terms. For example, it is not clear in the first portion (lines 6-9) why 6O2(g) becomes only one O2(g) because the 5O2(g) is to the right of the yields arrow. I suggest presenting this as three complete equations in a linear style (NIs needed). The reader will better be able to match the cancelled item if you do not break the equations apart. See attached braille file for an idea.