Lets say you were doing an experiment on two different chemicals in two different test tubes. One chemical is giving off oxygen gas or hydrogen gas the other is giving off carbon dioxide gas. What one test could you do in each test tube that would prove which is giving of the oxygen or hydrogen an which is giving off the carbon dioxide

Tests for gases

Hydrogen, oxygen, carbon dioxide, ammonia and chlorine can be identified using different tests.

Hydrogen. A lighted wooden splint makes a popping sound in a test tube of hydrogen.

Oxygen. A glowing wooden splint relights in a test tube of oxygen.

hope it will help

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

since electrons are negative the answer is neagtaive