How many molecules are in 4.5 L of #CO_2# at STP?

1 Answer
May 1, 2016

#(4.5*L)/(22.4*L*mol^-1)# #xx# #N_A#, where #N_A =" Avogadro's number"#

Explanation:

We assume ideality, and recall that at #"STP"# 1 mole of ideal gas occupies a volume of #22.4*L#. We also know that #N_A =" Avogadro's number"# #=# #6.02214xx10^23*mol^-1#

So #(4.5*L)/(22.4*L*mol^-1)# #xx# #6.02214xx10^23*mol^-1# #=#

#"approx. "1/5xxN_A?#

You can do the arithmetic.

How many atoms are there in this quantity?