How many #N_2O_4# molecules are contained in 76.3 g#N_2O_4#?

1 Answer
Aug 10, 2016

We work out (i) the number of moles of #N_2O_4#, and (ii) convert this to molecules.

Explanation:

#"Moles of dinitrogen tetroxide"# #=# #(76.3*g)/(92.011*g*mol^-1)#. This gives an answer in #"moles"#. Now it is a fact that in #1# #"mole"# of stuff there are #6.022xx10^23# individual items of that stuff:

#"Number of "N_2O_4" molecules"# #=# #6.022xx10^23mol^-1xx(76.3*g)/(92.011*g*mol^-1)# #=# #??" molecules."#