# Nitric Acid Molecular Weight Calculation

The molecular weight of Nitric acid (HNO3) is 63.012.

To calculate molecular weight of any compound, the first step is to know the constituent elements (atoms) and their number in that particular compound. Then calculate the total atomic weight of each element by multiplying its atomic weight by its number. The sum of total atomic weight of all constituent elements will be the molecular weight of the compound. Note that the value of atomic weight may differ from different sources. This is because some sources use conventional atomic weight while others use standard atomic weights. Another important point to consider is the isotopes of an element. Different isotopes of an element will have different atomic weights.

# CALCULATION PROCEDURE

Step 1: Find out the chemical formula and determine constituent atoms and their number in a Nitric acid molecule.
From the chemical formula, you will know different atoms and their number in a Nitric acid molecule. Chemical formula of Nitric acid is HNO3. From the chemical formula of Nitric acid, it is easy to find out that there are one Hydrogen (H) atom, one Nitrogen (N) atom and three Oxygen (O) atoms in a molecule of Potassium hydroxide.

Step 2: Find out atomic weights of each atom (from periodic table).
Atomic weight of Hydrogen (H) : 1.008 (Ref: Pubchem-Hydrogen)
Atomic weight of Nitrogen (N): 14.007 (Ref: Pubchem-Nitrogen)
Atomic weight of Oxygen (O) : 15.999 (Ref: Pubchem-Oxygen)

Step 3: Calculate the total weight of each atom present in Nitric acid by multiplying its atomic weight by its number.

Number of Hydrogen atoms in Nitric acid: 1
Atomic weight of Hydrogen: 1.008
Total weight of Hydrogen atoms in Nitric acid: 1.008 x 1 = 1.008

Number of Nitrogen atoms in Nitric acid: 1
Atomic weight of Nitrogen: 14.007
Total weight of Nitrogen atoms in Nitric acid: 14.007 x 1 = 14.007

Number of Oxygen atoms in Nitric acid: 3
Atomic weight of Oxygen: 15.999
Total weight of oxygen atoms in Nitric acid: 15.999 x 3 = 47.997

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

Molecular weight of Nitric acid (HNO3):
1.008 (1.008 x 1 Hydrogen) + 14.007 (14.007 x 1 Nitrogen) + 47.997 (15.999 x 3 Oxygen)

So the molecular weight of Nitric Acid is 63.012.