The molecular weight of Sodium phosphate monobasic [NaH₂PO₄] is 119.977131278.

Sodium phosphate monobasic (NaH₂PO₄), also called Monosodium phosphate or monobasic sodium phosphate, is an inorganic compound of four elements: Sodium, Hydrogen, Phosphorus, and Oxygen. The molecular weight of Sodium phosphate monobasic is 119.977131278 which can be calculated by adding up the total weight (atomic weight multiplied by their number) of all its elements.

CALCULATION PROCEDURE: Sodium phosphate monobasic  [NaH₂PO₄] Molecular Weight Calculation

Step 1: Find out the chemical formula and determine constituent atoms and their number in a Sodium phosphate monobasic molecule.
From the chemical formula, you will know different atoms and their number in a Sodium phosphate monobasic molecule. The chemical formula of Sodium phosphate monobasic is NaH₂PO₄. From the chemical formula of Sodium phosphate monobasic, you can find that one molecule of Sodium phosphate monobasic consists of one Sodium (C) atom, two Hydrogen (H) atoms, one Phosphorus (P) atom, and four Oxygen atoms.

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

Atomic weight of Sodium (Na): 22.98976928 (Ref: Ciaaw-sodium)
Atomic weight of Hydrogen (H): 1.008 (Ref: Lanl-1)
Atomic weight of Oxygen (O): 15.9994 (Ref: Jlab-ele008)
Atomic weight of Phosphorus (P): 30.973761998 (Ref: Jlab-ele015)

Step 3: Calculate the total weight of each atom in a Sodium phosphate monobasic molecule by multiplying its atomic weight by its number.

Number of Sodium atoms in Sodium phosphate monobasic: 1
Atomic weight of Sodium (Na): 22.98976928
Total weight of Sodium atoms in Sodium phosphate monobasic: 22.98976928 x 1 = 22.98976928

Number of Hydrogen atoms in Sodium phosphate monobasic: 2
Atomic weight of Hydrogen (H): 1.008
Total weight of Hydrogen atoms in Sodium phosphate monobasic: 1.008 x 2 = 2.016

Number of Phosphorus atoms in Sodium phosphate monobasic: 1
Atomic weight of Phosphorus (P): 30.973761998
Total weight of Phosphorus atoms in Sodium phosphate monobasic: 30.973761998 x 1 = 30.973761998

Number of Oxygen atoms in Sodium phosphate monobasic: 4
Atomic weight of Oxygen (O): 15.9994
Total weight of Oxygen atoms in Sodium phosphate monobasic: 15.9994 x 4 = 63.9976

Step 4: Calculate the molecular weight of Sodium phosphate monobasic by adding up the total weight of all atoms.

Molecular weight of Sodium phosphate monobasic: 22.98976928 (Sodium) + 2.016 (Hydrogen) + 30.973761998 (Phosphorus) + 63.9976 (Oxygen) = 119.977131278

So the molecular weight of Sodium phosphate monobasic is 119.977131278.

Sodium phosphate monobasic [NaH₂PO₄] Molecular Weight Calculation

REFERENCES:

• Lanl-1: https://periodic.lanl.gov/1.shtml 
• Ciaaw-sodium: https://www.ciaaw.org/sodium.htm
• Jlab-ele008: https://education.jlab.org/itselemental/ele008.html
•  Jlab-ele015: https://education.jlab.org/itselemental/ele016.html
  

See also:

• Hydrogen chloride molecular weight calculation