1. If liquids can be separated into layers of density, could gases also be separated? Explain your reasoning.

Hey there! I'll try to provide you with my best answer.

The main reason why it probably wouldn't be seperated is because the molecules in gas are much farther away from each other. This created a huge gap within the two states so sometimes it's likely to be not seperated. But it solely depends on the sort of gas is being used. If they have higher density difference then it is possible to be seperated.

If air is included as gas then yes, because there is heavy and light air. The heavy air is the cold air which you feel at night. Meanwhile the light air the warm air which rises in the sky during day light. Both of them are seperated because of their densities. Or atleast they are seperated into layers themselves. For example: this slightly cold and hot air is felt when your nearby a camp fire.

Hope it made sense.

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.