Setup

the setup considered of
1.two plastic tubes 
2.one plastic lid
3.one piece of clear tubing
4.one 9 volt alkaline battery (left)
5.1/4 cup of table salt (left)
5.1/4 cup of water (both)
6.one basic household lighter


the cathode in this Electrolysis experiment is the negative terminal of the battery, and the anode the positive terminal. we are not separating the oxygen and hydrogen gases from these terminals and they are mixed as they rise and go through the tube. when they are mixed they create a Oxyhydrogen gas this is a very powerful gas and has a low required ignition energy to combust. the tube on the right acts as a "one way water valve", it doesn't allow a ignition source to go further along the tub and spark a rapid ignition. because of this valve all that should be produced is slow and steady amounts of Oxyhydrogen gas, in the form of bubbles on the surface of the water.