How do you calculate the mass of one mole of such hydrogen giving your answer to atoms four decimal places? (The Avogadro constant, L= #6.0225 xx 10^23 mol^-1#)?

1 Answer
Jan 7, 2017

Answer:

#"Mass of 1 mole of hydrogen atoms"# #=# #"Mass of 1 hydrogen atom"xx"N"_A#, where #"N"_A=L=6.0225xx10^23*mol^-1#.

Explanation:

#"Mass of 1 hydrogen atom"# #=# #1.6727xx10^{-27}*"kg"# (from this site).

And thus, #"mass of 1 mole of hydrogen atoms"# #=#

#1.6727xx10^(-27)*"kg"xx6.0225xx10^23*mol^-1xx10^(3)*"g"*kg^-1#

#=1.007*"g"*"mol"^-1#

Clearly, you would not be expected to know these masses. You would be expected to be able to do such a calculation if provided with the masses of the nucleon, and with #"Avogadro's number"#.

What is the mass of one mole of hydrogen molecules?