The molecular weight of Arginine [(H2N)(HN)CN(H)(CH2)3CH(NH2)COOH] is 174.20196.

Arginine ((H2N)(HN)CN(H)(CH2)3CH(NH2)COOH) is an organic compound of four elements: Carbon, Hydrogen, Nitrogen, and Oxygen. The molecular weight of Arginine is 174.20196 which can be calculated by adding up the total weight (atomic weight multiplied by their number) of all its elements.

CALCULATION PROCEDURE: Arginine  [(H2N)(HN)CN(H)(CH2)3CH(NH2)COOH] Molecular Weight Calculation

Step 1: Find out the chemical formula and determine constituent atoms and their number in an Arginine molecule.
From the chemical formula, you will know different atoms and their number in an Arginine molecule. The chemical formula of Arginine is (H2N)(HN)CN(H)(CH2)3CH(NH2)COOH. From the chemical formula, you can find that one molecule of Arginine consists of six Carbon (C) atoms, fourteen Hydrogen (H) atoms, four Nitrogen (N) atoms, and two Oxygen atoms.

Step 2: Find out the atomic weights of each atom (from the periodic table).

Atomic weight of Carbon (C): 12.0107 (Ref: Jlab-ele006)
Atomic weight of Hydrogen (H): 1.008 (Ref: Lanl-1)
Atomic weight of Nitrogen (N): 14.00674 (Ref: Jlab-ele007)
Atomic weight of Oxygen (O): 15.9994 (Ref: Jlab-ele008)

Step 3: Calculate the total weight of each atom in an Arginine molecule by multiplying its atomic weight by its number.

Number of Carbon atoms in Arginine: 6
Atomic weight of Carbon (C): 12.0107
Total weight of Carbon atoms in Arginine: 12.0107 x 6 = 72.0642

Number of Hydrogen atoms in Arginine: 14
Atomic weight of Hydrogen (H): 1.008
Total weight of Hydrogen atoms in Arginine: 1.008 x 14 = 14.112

Number of Nitrogen atoms in Arginine: 4
Atomic weight of Nitrogen (N): 14.00674
Total weight of Nitrogen atoms in Arginine: 14.00674 x 4 = 56.02696

Number of Oxygen atoms in Arginine: 2
Atomic weight of Oxygen (O): 15.9994
Total weight of Oxygen atoms in Arginine: 15.9994 x 2 = 31.9988

Step 4: Calculate the molecular weight of Arginine by adding up the total weight of all atoms.

Molecular weight of Arginine: 72.0642 (Carbon) + 14.112 (Hydrogen) + 56.02696 (Nitrogen) + 31.9988 (Oxygen) = 174.20196

So the molecular weight of Arginine is 174.20196.

Arginine [(H2N)(HN)CN(H)(CH2)3CH(NH2)COOH] Molecular Weight Calculation

REFERENCES:

• Lanl-1: https://periodic.lanl.gov/1.shtml 
• Jlab-ele006: https://education.jlab.org/itselemental/ele006.html 
• Jlab-ele007: https://education.jlab.org/itselemental/ele007.html
• Jlab-ele008: https://education.jlab.org/itselemental/ele008.html
  

See also:

• Hydrogen chloride molecular weight calculation