An amino acid contains 52.2% carbon, 9.3% hydrogen, 8.7% nitrogen and 29.8% oxygen by mass and has a relative molecular mass of 161 g/mol. What is its molecular formula? What functional groups must it have?

In 100g of compound, the amount of each element is given by: C: n = 52.2/12 = 4.35 H: n = 9.3/1 = 9.3 N: n = 8.7/14 = 0.621... O: n = 29.8/16 = 1.8625 Dividing through by the smallest amount (0.621) gives: C: 7.0048..., H: 14.9758..., N: 1, O: 2.9991... These are all very close to whole numbers so the empirical formula is C7H15NO3. This has a relative formula mass of 161 so the molecular formula is also C7H15NO3. As this compound is stated to be an amino acid it must contain both an amine and a carboxylic acid group.

GB
Answered by Georgina B. Chemistry tutor

2814 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

Explain why the 2nd Electron aiffinity of Chlorine is Endothermic whilst the first electron affinity is exothermic


Part 1: Calculate the empirical formula for a substance with the following composition: H 6.71%; C 40.00%; O 53.29%


A solution of acetic acid and sodium acetate was prepared, by dissolving 4.1 g of sodium acetate in 750 cm^3 of 0.085 mol/dm^3 acetic acid, at 25 degrees. 10 Cm^3 of 2 mol/dm^3 HCl was added. Ka is 1.76*10^-5, calculate and explain the change in pH


Define and give an example of Le Chatalier's Principle of Chemical Equilibrium.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning