In: Chemistry
Q. A certain amino acid has the following elemental composition: C, H, O, N. In a combustion analysis, 3.263g of it was combusted to produce 5.910g of CO2 and 2.835g of H2O. Separate analysis determined that it is 19.17% N, and its molar mass is 150g/mol. Determine its empirical and molecular formula.
Step 1) Determine the mass of C, H, O and N
Carbon:
= 1.613 g
Hydrogen :
= 0.3175 g
Nitrogen =
=0.626 g
mass of Oxygen = Mass of compound -(mass of C + H+N)
Mass of O = 3.263 - (1.613 +0.626+0.3175) =0.7065 g
Step 2) Percentage of C, H, N and O
percentage of C =
C =49.43%
percentage of H =
H =9.73%
Percentage of N =19.17%
Percentage of O =
O=21.65%
Step 3) Determine empirical formula