Nitrogen Percentage Calculation

Question

An organic amine has a molar mass of 73 g mol^-1 and contains a single nitrogen atom per molecule; what is the percentage by mass of nitrogen present in this compound?

RankGuru · Accepted Answer

The mass percentage of an element in a compound is found by dividing the total mass of that element in one mole by the molar mass of the compound and multiplying by one hundred. Here each molecule contains exactly one nitrogen atom, whose atomic mass is 14 g mol^-1, and the molar mass of the amine is given as 73 g mol^-1. Therefore the nitrogen percentage equals (14/73) × 100, which is approximately 19.2%. The option 14.0% mistakenly reports the atomic mass of nitrogen as if it were a percentage and is dimensionally meaningless here. The option 23.3% would correspond to a smaller molar mass of about 60 g mol^-1, not 73, so it does not match the data. The option 9.6% would require two nitrogen-free dilution or a much larger molar mass and is inconsistent with a single nitrogen in a 73 g mol^-1 molecule. This type of elemental composition calculation underlies Duma's and Kjeldahl's nitrogen estimation methods discussed in NCERT. As a plausibility check, a molar mass of 73 with one nitrogen fits a C4H11N amine such as butylamine, and 14 of 73 being just under one-fifth confirms the 19.2% result.

Nitrogen Percentage Calculation

Select the correct option:

🔒 Solution Hidden from View

More organic compounds containing nitrogen Practice Questions

An amide is treated with bromine and aqueous potassium hydroxide, producing a primary amine that con...

Ethylamine is warmed with chloroform and alcoholic potassium hydroxide, and an offensive-smelling pr...

To replace the diazonium group of benzenediazonium chloride with a chlorine atom on the ring, which ...

Catalytic hydrogenation of propanenitrile in the presence of nickel yields a saturated primary amine...

Why must the diazotization of aniline with sodium nitrite and hydrochloric acid be carried out while...

Benzenediazonium chloride is treated with copper powder in the presence of hydrobromic acid; which n...

On exhaustive methylation followed by heating of the quaternary ammonium hydroxide, an unsymmetrical...

Aniline is treated with acetic anhydride to form acetanilide, and this acetylation is performed befo...

A mixture of primary, secondary, and tertiary amines is separated using the Hinsberg reagent followe...

Benzenediazonium chloride is warmed with hypophosphorous acid in water, and nitrogen gas is evolved;...

Three amines, namely ethylamine, N-methylethanamine, and N,N-dimethylethanamine, are each treated wi...

An alkyl halide is heated separately with potassium cyanide and with silver cyanide; how do the majo...

About This Question

Solution