# Question #90983

Feb 8, 2015

Based on molecular weight alone we can qualitatively arrange these

Electron, Proton, Atom, Hydrogen, Sodium Chloride, Carbonic acid, Amino acid, Glucose, Triglyceride, Protein

First three are self explanatory. Sodium chloride has molecular weight of around 58.

Carbonic acid is Phenol which is ${C}_{6} {H}_{7} O$ constitutes to a molecular weight of around 95.

Lowest known amino acid has molecular weight of around 75. Hence this can be swapped with phenol position based on the choice of amino acid. Only 2 of them have molecular weight less than 95. So I am allotting this position to amino acid.

Glucose which is ${C}_{6} {H}_{12} {O}_{6}$ has molecular weight of 180.

Triglycerides are generally esters of higher carboxylic acids with Glycerol. Glycerol itself has a molecular weight of 93.

Protein is a polymer of amino acids. Hence it has the highest molecular weight.

Feb 8, 2015

Based on relative mass, the order is:

electron < proton < hydrogen molecule < atom < sodium chloride < carbonic acid < amino acid < glucose < triglyceride < protein.

Electrons and protons are parts of an atom, and electrons have less mass than protons.

The mass of an electron is about 0.0005 u.

The mass of a proton is about 1 u.

The mass of a molecule of H₂ is about 2 u.

The masses of atoms range from 1 u to 294 u. Only 1 atom, H, has a mass less than 2 u, so I would put atoms after hydrogen molecules. The most abundant atoms in the earth's crust have atomic masses less than 58 u.

Sodium chloride does not consist of molecules. The molecular mass of a formula unit of NaCl is about 58 u.

Carbonic acid is ${\text{H"_2"CO}}_{3}$. It has a molecular mass of about 62 u.

The molecular masses of the common amino acids range from 57 to 186 u. Only one has a molecular mass greater than 180 u.

Glucose is ${\text{C"_6"H"_12"O}}_{6}$. It has a molecular mass of about 180 u.

Triglycerides are esters of long-chain carboxylic acids with glycerol. Tristearin is a typical triglyceride. It has a molecular mass of about 891 u.

Proteins are polymers of amino acids. Their molecular masses range from 50 000 u to 3 000 000 u.