🧪 Grams to Moles Calculator
Convert grams to moles instantly using the formula n = m / M. Enter the mass in grams and the molar mass of the substance.
What Is a Mole?
A mole is the SI unit for measuring the amount of a substance. One mole contains exactly 6.02214076 × 10²³ elementary entities (atoms, molecules, ions, etc.) — a number known as Avogadro's constant. The mole bridges the microscopic world of atoms and molecules with the macroscopic world of grams and kilograms.
What Is Molar Mass?
Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). It is numerically equal to the substance's relative atomic or molecular mass, but with units.
- Water (H₂O): 2 × 1.008 + 15.999 = 18.015 g/mol
- Carbon Dioxide (CO₂): 12.011 + 2 × 15.999 = 44.01 g/mol
- Sodium Chloride (NaCl): 22.99 + 35.45 = 58.44 g/mol
How to Convert Grams to Moles
The conversion uses the fundamental formula:
n = m ÷ M
Where: n = number of moles (mol) | m = mass (g) | M = molar mass (g/mol)
Example: How many moles are in 50 grams of water (H₂O)?
- Molar mass of H₂O = 18.015 g/mol
- moles = 50 g ÷ 18.015 g/mol = 2.775 mol
Why Use This Grams to Moles Calculator?
- Instant Conversion: Get accurate mole calculations in seconds.
- Common Compounds: Select from a list of common substances to auto-fill molar mass.
- Step-by-Step Details: See the exact calculation broken down.
- Visual Chart: Understand the relationship between mass, molar mass, and moles.
- Free & Private: No registration, no data storage.
❓ Grams to Moles Calculator FAQ
What is the formula to convert grams to moles?
The formula is n = m ÷ M, where n is moles, m is mass in grams, and M is molar mass in g/mol.
What is molar mass?
Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). It is numerically equal to the relative atomic or molecular mass.
What is Avogadro's number?
Avogadro's number is 6.02214076 × 10²³ — the number of entities (atoms, molecules, etc.) in one mole of a substance.
How many moles are in 1 gram of water?
1 gram of water (H₂O, molar mass 18.015 g/mol) contains 1 ÷ 18.015 = 0.0555 moles.
What is the molar mass of CO₂?
The molar mass of carbon dioxide (CO₂) is 44.01 g/mol (12.011 + 2 × 15.999).
How do I calculate molar mass of a compound?
Add the relative atomic masses of all atoms in the chemical formula. For example, H₂O = 2 × 1.008 + 15.999 = 18.015 g/mol.
Can I use this calculator for any substance?
Yes, as long as you know the molar mass of the substance. You can enter any molar mass value manually.
What is the difference between molar mass and molecular weight?
Molar mass and molecular weight are often used interchangeably. However, molar mass has units (g/mol), while molecular weight is a dimensionless relative value.
Is this calculator free?
Yes, this calculator is completely free to use. No registration or personal data storage is required. All calculations are performed in your browser.
What is a mole in chemistry?
A mole is the SI unit for amount of substance. It represents 6.022 × 10²³ particles (atoms, molecules, ions, etc.).
How many moles are in 100 grams of sodium chloride?
NaCl has a molar mass of 58.44 g/mol. 100 g ÷ 58.44 = 1.711 moles.
What is the molar mass of sulfuric acid?
The molar mass of H₂SO₄ is 98.078 g/mol (2 × 1.008 + 32.065 + 4 × 15.999).
How do I convert moles to grams?
Use the inverse formula: m = n × M. Multiply the number of moles by the molar mass to get grams.
What is the molar mass of glucose?
Glucose (C₆H₁₂O₆) has a molar mass of 180.16 g/mol (6 × 12.011 + 12 × 1.008 + 6 × 15.999).
How accurate is this calculator?
This calculator uses standard atomic masses and provides results to the precision you select. For exact scientific work, consult the latest IUPAC values.