How many hydrogen molecules are in 2.75 L of #H_2# gas at STP?

1 Answer
Jun 27, 2016

#(2.75*L)/(22.4*L*mol^-1)xx6.022xx10^23" hydrogen molecules mol"^-1# #=# #??"hydrogen molecules"#

Explanation:

The molar volume of an ideal gas at #"STP"# is #22.4*L#.

We assume (reasonably) that dihydrogen behaves ideally, and mulitply the quotient of volumes by #"Avogadro's number, " N_A, 6.022xx10^23*mol^-1# to give an answer in numbers of hydrogen molecules.

How many hydrogen atoms in such a quantity?