Exercise (l):
Toxicity of aspartame
The objective of this exercise is to determine the molecular formula of aspartame (CxHyOzN) and to study
the effect of hydrolysis, of aspartame in light soft drink
Given:
Molar mass in g mol: H=1C=12, N = 14, O = 16 and aspartame = 294 Vx=24 L mol
1- Elemental analysis of Aspartame:
In order to determine us molecular formula, we release an elemental analysis of two samples of
aspartame:
• Sample (1): The complete combustion of 441 mg of aspartame released mass m (in mg) of carbon
dioxide and 242.9 mg of water.
Sample (2): 31.5 mg of aspartame liberates a volume V = 2.571 mL of nitrogen gas No
1.1- Knowing that the % by mass of carbon element in aspartame is 57.14%. Calculate the mass m of
CO2 released
1.2- Describe an experimental procedure allows to prove there is nitrogen element.
1.3- Show that the % by mass of nitrogen element in aspartame is 9.52%
1.4. Calculate the percent by mass of hydrogen and oxygen elements.
1.5- Show that the molecular formula of aspartame is C14H1sOsN2.