OK, I'm clueless. I have this one homework problem where I am asked to represent a reaction with a "sphere equation". I have no idea what this is and I can't locate it in my book. Wasn't mentioned during lecture either. Does anyone know what this means? Here's the whole problem (maybe it will make sense in context): a) write a chemical equation for the complete combustion of ethane. b) represent this equation with Lewis structures. c) represent this reaction with a sphere equation.