# Chemistry

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A two-liter plastic soft drink bottle can withstand a pressure of 5.00 atm. Half a cup (approximately 120mL) of ethyl alcohol, (d=0.789g/mL) is poured into a soft drink bottle at room temperature. The bottle is then heated to 100C (3sig figs), changing the liquid alcohol to a gas. What is the pressure caused by the gas?

Pf= 4.65(.120)/297 x 373/.120 = 5.84
Can some one let me know if this is correct

• Chemistry - ,

Determine the number of moles, n, from the amount of ethyl alcohol added. Then use

P = nRT/V to get the partial pressure due to alcohol, assuming it all evaporates.

That does not look like what you did. I do not understand your calculation. It looks like the 0.120 l would cancel out, and that isn't right.

There will also be an additional partical pressure due to air that was present when the bottle was sealed.

• Chemistry - ,

This is a second posting of the same question. The 120 mLs are a liquid volume and should be used only to get the mass of the alcohol. The volume of the gas would be the same as the volume of the flask. At 100 degrees C, all the alcohol would have been changed to gas with a volume of 2.00 liters.