Hardcore Chemistry question...?

Question

Estimate the number of moles of gas (and mass of gas assuming that it is all N2) inside your family car (or a friends if you don't have one). If the amount of gas was compressed at constant temperature to fit inside a coke can what would the pressure inside the coke can be?

Wow, vincent. Well done.

You gave everything I needed to know. Thanks

Answer 1

Ok, well a compact car, if you used that for an example, has a 3000L interior, and an ideal gas at standard conditions has 22.4 liters per mole, than the interior would hold 133.9 moles of N2. The volume of a soda can is 415 ml, or .415 L so if you plug that into the ideal gas law, (PV=nRT) and solve for pressure you get 8247.03 atm.

Answer 2

That is kind of a nasty question, beacsue it requires knowledge outisde of chemistry. here is the interoir volume of cars, as a function of their classification:

Sedans
Minicompact < 85
Subcompact 85 to 99
Compact 100 to 109
Mid-Size 110 to 119
Large 120 or more


Station Wagons
Small <130
Mid-Size 130 to 159
Large 160 or more


Volume is in cubic feet, which is 28.317 l. So for the average mid-size sedan 115 ft^3, you get 3256 l, or (at zero C) 145.4 moles (all numbers are rounded) since one mole of gas is supposed to occupy 22.4 l at zero C. Nitrogen is 28 g/mole, so you would have just over 4 kg of gas.

Now, a can of coke is 355 ml, or 0.355 l. Assuming you could compress the gas from 3256 l down to 0.355 l, the pressure would be 9172 atmosphere. But at that pressure, I am pretty sure the nitrogen would haveto be liquid already, so this is an impossible feat (and that is assuming a small can could resist that much pressure).

Does this answer your question?

Answer 3

You need to know the volume of the car first. Not all cars have the same volume,mass,shape etc. The coke can is 355ml. So you can solve that one. So if you emptied the Coke can and vacuumed out all of the air. Then filled it up with Nitrogen . You would have a Volume of 355ml of Nitrogen. From the formula for Density; D=M/V.You can solve for M by re-arranging the formula to give; M=V*D. Now,you need to get M. Mass is determined by the elements atomic mass unit in grams. Take the value of Nitrogen's amu. Divided it by the volume (355ml). Use this in the next formula; M=V*D. To get the actual number of grams of Nitrogen in the can. To obtain the number of moles. Multiply The mass time 6.022 * 10^23( a mole). As for the pressure. The pressure would be the same as the atmospheric pressure outside the can. If you filled the can up to it's full capacity. If it was more. The can would burst. If it was less. It would collapse. Just like in an airplane. I did this in a hurry. Double check the steps.If it's wrong.

Answer 4

3

Answer 5

The pressure would be zero because the coke can would blow from the excess pressure.