15 Each Points Please Help ASAP Will Mark Brainliest If All Are Answered!!

Why do cells appear different in distilled water than they do in 10% salt water?

How many valence electrons are in atom of radon?

Butane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix butane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 390 mmhg, what is the pressure (in mmhg) of water vapor after the reaction is completed (temperature and volume do not change).