Question:chemistry basic question, just need other ideas. please answer with any experiment that demonstrates that air exerts pressure, and how. thank you!

Answers:the magdeburg hemisphere experiment http://en.wikipedia.org/wiki/Magdeburg_hemispheres

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Question:1. Inflating a ballon and weighing the mass of it and then releasing the most of the gas from the balloon and weighing the mass of it. 2. Placing an empty drinking glass in a container of water with its end facing downward and tilting it. 3. inserting an unused balloon in a bottle and then blowing it up in the bottle. 4. inflating 2 balloons and putting one in ice water and the other in boiling water.

Answers:1- prove it is a matter ( it has a mass so it is a matter) 2- if u do the secon one ull see water can not get in the glass (try it at home) so it means it exerts a pressure more than the water to keep it out. 3- i didnt understan what does it say 4- in these case the one in the ice will get smaller becaeuse of the cold and the one in the boilin water will expand it also proves that it is a matter it expands with heat and streches with cold

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Question:1. Placing a boiling hot aluminum can in ice water. 2. Filling a test tube with water and putting a piece of plastic on it and turning it upside down.(the water does not come out) 3. Putting in air in a syringe and putting a cap on the end, later holding the cap in placegently pushing the plunger down with your thumb and releasing the plunger. 4. Putting an unused balloon inside a bottle and then trying to blow it up while the balloon is in the bottle.

Answers:2 means that there is a pressure holding the water in the tube so two proves 3 three also proves it air pus the cap out so it means it exerted a pressure 4 if u exert enough pressure it will break the bottle so 4 is also checked 1 i couldnt find the relation of it with the air i dont think it does not prove not sure

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Question:

Answers:mass: take a meter stick and tape two uninflated balloons on either end of the stick, marking carefully where you place the balloons...now, balance the stick (with the balloons on it) so there is equal mass on either side of the balance point... carefully remove ONE of the balloons, and blow it up, being very careful to retape it to the same spot it was on before now you will see that the meter stick is NOT balanced and tilts in the direction of the inflated balloon, showing there is additional mass in the balloon once you have inflated it pressure: take a meter stick and place it on a table with a small portion of it hanging over the edge take a newspaper and use the newspaper to cover up the meter stick that is still on the table..make sure you cover all of the meter stick...now, squeeze out all the air from underneath the paper once you have done that, see what happens when you "chop down" on the overhanging portion of the stick...it will barely move no matter how hard you hit it...in fact, if you did a really good job squeezing out the air from underneath the paper, you might snap the stick in two this is because the pressure of the air is bearing down on the surface area of the paper, holding the meter stick down

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