Three classical examples of seeing the ideal gas law in action:
crumpled water bottle in cold car
crumpled water bottle after your flight lands
fridge door harder to open a second time after first.
I'm afraid I'm having trouble understanding all three, and I believe it stems from a single reason: the derivation of the ideal gas law is for a closed container subject to the conditions of temperature, pressure, volume, number of moles in THAT closed container. The explanations I see regarding these every day problems are either vague in regards to which quantities in the gas law are considered as being held constant, or vague in regard to describing the conditions IN the container; they always tend to talk about conditions outside the container. What am I missing here? Can someone elaborate, specifically telling me which variables are considered constant in each case, and which are fluctuating and why?