My son is trying to write a conclusion for a basic decomposition of water experiment using a 9 V battery (with a test tube placed over each terminal) placed inside a salt water solution. The results were: the tube over the negative terminal nearly completely filled with presumably hydrogen gas while the tube over the positive terminal only had a minute amount of presumably oxygen gas.
His textbook didn't explain these results, other than to hint at the fact that the results were due to there being twice as many hydrogen atoms in the product. He has several questions that I cannot answer.
- If the hydrogen and oxygen molecules take up the same amount of space, then why did the tube over the negative terminal have much more than twice the gas as the other one?
- The atomic mass of oxygen is nearly 16 times that of hydrogen, so then even if there was twice as much hydrogen in the product, wouldn't the oxygen still take up more space?