When elements bond, what is the part of the atom doing the bonding?

For the following reaction, 5.65 grams of oxygen gas are mixed with excess hydrochloric acid . assume that the percent yield of water is 86.4 %. hydrochloric acid(aq) + oxygen(g) water(l) + chlorine(g) what is the ideal yield of water ? grams what is the actual yield of water ? grams

For the following, determine the type of reaction and then give products.

1) which of the following is the best example of a physical change? a) sugar dissolving in tea b) firefly glowing 2) in the combustion of ethane, what is/are the reactants? c2h6 + o2 ==> co2 + h2o a) c2h6 and o2 b) co2 and c2h6