what experiment observation suggest a gas is being released?

Answer 1

Huh? I think you need to be more clear.

Answer 2

Depends what gas you're talking about evolving. Generally, a simple way to test for gas evolution is carry out the reaction in a closed chamber (like a test tube), and put something over it like a balloon that can expand, if you're getting gas out then the balloon will blow up, otherwise it won't.

For specific gases, there are often simple tests that can nearly conclusively prove the evolution of a gas. If you could be more specific, some could be suggested.

Answer 3

In a chemical reaction, if gas is being released, bubbling is the first indicator and smell (if the gas has any smell) is the next. If the reaction is being carried out in a closed system, rise in pressure (indicated by a sensor or pressure gauge) will be another.

Answer 4

From what I understand from your question, I think that a flexible film-like wrapper, such as a ziploc bag or loose plastic wrap that fits over the experiment (assuming that it's a beaker like container). If it begins to bulge outwards, for most experiments, this means that a gas was emitted.

Answer 5

You need more detail to help. Anyway, if you suspect a gas, try to collect a sample. In an experiment, just basically you should know what gas to expect, just devise a way to collect it.

Answer 6

Formation of bubbles in a solution is a good bet.