1. What is Molar Mass?

Molar mass is the mass of one mole of a substance (chemical element or chemical compound). It is a physical property defined as the mass of a given substance divided by the amount of substance.

2. How is Molar Mass Calculated?

The molar mass is calculated using the formula:

Where:

• Atomic Masses — The standard atomic weight of each element (from periodic table)
• Coefficients — The subscript numbers in the chemical formula

Example: For H₂O (water):

• 2 × (1.008 g/mol for Hydrogen) = 2.016 g/mol
• 1 × (15.999 g/mol for Oxygen) = 15.999 g/mol
• Total molar mass = 2.016 + 15.999 = 18.015 g/mol

3. Importance of Molar Mass

Details: Molar mass is essential for converting between mass and moles of a substance, which is fundamental in stoichiometric calculations in chemistry.

4. Using the Calculator

Tips: Enter the chemical formula using standard notation (e.g., H2O, C6H12O6). The calculator will sum the atomic masses of all atoms in the formula.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between molecular mass and molar mass?
A: Molecular mass is the mass of one molecule, while molar mass is the mass of one mole (6.022×10²³ molecules) of a substance.

Q2: How do I calculate molar mass for hydrates?
A: Include the water molecules in the formula (e.g., CuSO₄·5H₂O) and calculate their mass along with the main compound.

Q3: Where can I find atomic masses?
A: Standard atomic masses are listed in the periodic table. The calculator uses the most common isotope masses.

Q4: Does this work for ionic compounds?
A: Yes, the same principle applies. For example, NaCl has a molar mass of 22.99 (Na) + 35.45 (Cl) = 58.44 g/mol.

Q5: How accurate are these calculations?
A: The accuracy depends on the precision of the atomic masses used. Most calculations use atomic masses to 2-4 decimal places.