What is the percent composition by mass of aspartame #C_14H_18N_2O_5#?

1 Answer
Feb 19, 2016

Answer:

I will solve for percentage composition of #N# in the compound.

Explanation:

Molecular mass of aspartame:
#=# #(14xx12.011+18xx1.00794+2xx14.011+5xx15.999)*g*mol^-1#

#=# #294.31# #g*mol^-1#.

But we want the percentage composition of nitrogen in the sample:

#(2xx14.011*g*mol^-1)/(294.31*g*mol^-1)# #xx# #100%# #=# #??%#

Note that the sum of the individual elemental percentages must equal 100%. Why??