Molar Mass Calculator

Calculate the molar mass (molecular weight) of any chemical formula.

๐Ÿงช

Calculation Parameters

Specify your chemical inputs.

Calculated Result

Molar Mass
18.015 g/mol
๐Ÿ’ก

Expert Tip

Double check molecular weights and balance equations to ensure stoichiometric ratios are correct.

How this Calculator Works

This calculator computes the molar mass of any given chemical formula by summing the standard atomic weights of its constituent elements. Enter the formula in the text input below:

  • Chemical Formula: A compound formula like H2O, CO2, or NaCl (Default: H2O)

The results are computed instantly and updated in the results panel on the right.

Formula & Methodology

Molar Mass = ฮฃ (Atomic Mass_i * Quantity_i)

Where:

  • Atomic Mass_i: The periodic atomic weight of element i (g/mol).
  • Quantity_i: The number of atoms of element i in the compound formula.

Step-by-Step Calculation Example

To calculate the molar mass of water ($H_2O$) manually, follow these steps:

  1. Identify the input parameters. For example:
    • Formula = H2O
    • Atomic Mass (H) = 1.008 g/mol, Quantity = 2
    • Atomic Mass (O) = 15.999 g/mol, Quantity = 1
  2. Apply the formula:
    Molar Mass = (1.008 * 2) + (15.999 * 1) = 2.016 + 15.999 = 18.015 g/mol
  3. Verify the calculated value which is updated instantly in the results panel on the right.

Frequently Asked Questions

What is molar mass? โ–ผ

Molar mass is the mass of one mole of a chemical substance, expressed in grams per mole (g/mol).

How do you calculate molar mass from a formula? โ–ผ

Sum the atomic masses of all constituent atoms in the chemical formula multiplied by their subscript frequencies.

Is molar mass numerically equal to molecular weight? โ–ผ

Yes, molar mass in g/mol has the exact same numerical value as molecular weight in atomic mass units (amu).

Related Calculators

View All Chemistry Tools →