Question #ac924

1 Answer
Jan 16, 2017

Approx. #0.029*mol# of benzene.................And the number of moles is equal to the number of benzene molecules.

Explanation:

We need to find the molar quantity of benzene, and thus we simply perform the operation:

#"Mass"/"Molar mass of benzene"# to give an answer in moles, #=#

#(2.24*cancelg)/(6xx12.011*cancelg*mol^-1+6xx1.00794*cancelg*mol^-1)#

#=0.0287*mol#.

Note that this is dimensionally consistent, because, #1/("mol"^-1)=1/(1/"mol")="mol"#

So there are #0.0287*mol# of benzene #"molecules"#.

And since #1*mol-="Avogadro's number of molecules"# #=# #6.022xx10^23*mol^-1#

And #=0.0287*mol*"benzene molecules"xx6.022xx10^23*mol^-1="How many benzene molecules?"#

And #"how many atoms?"#, #=0.0287*molxx12*"atoms"*mol^-1xx6.022xx10^23*mol^-1="How many atoms?"#

Why did I need to multiply the molar quantity by #"12 atoms?"#