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

Related Chemistry A Level answers

All answers ▸

Lead (IV) oxide reacts with concentrated hydrochloric acid as follows: PbO2(s) + 4HCl(aq) -----> PbCl2(s) + Cl2(g) + 2H2O(l) What mass of lead chloride would be obtained from 37.2g of PbO2, and what mass of chlorine gas would be produced


How does the reducing ability of halide ions vary?


Draw an Alkane with the molecular formula C4H8 as well as a possible functional group isomer and state a chemical test you can use to differentiate between the two.


Explain how a hydroxynitrile is produced from a ketone