How many moles of hydrogen gas occupy a volume of 0.25L at STP?

There are 0,011 moles of hydrogen gas.

Explanation:

We use the ideal gas formula, with the constant R = 0.082 l atm / K mol. The STP conditions are : 1 atm pressure and 273 K temperature. Solve for the formula, n (number of moles):

PV=nRT ---> n= (PV)/(RT)

n= (1 atm x 0,25 L)/ (0,082 l atm/ K mol x 273 K)

n= 0,011 mol

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

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