General Chemistry : for Nursing
posted by Shayla .
Im Having a really Hard time with this problem :(
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A sample containing 5.60g O2 gas has a volume of 31.0L . Pressure and temperature remain constant.
1 .) Oxygen is released until the volume is 8.00L . How many moles of O2 are removed?

PV = nRT; so if P, R and T are constant, that means V = n*k and n = grams/molar mass
You had 5.60/32 = 1.75 mols O2 to start. You end up with 8.00 which means you lost 31.08.00 = 23 L. How many mols is that? 1.75 x 23/31 = ?