Science

Mole to Grams Calculator

Convert moles to grams using molar mass with step-by-step chemistry help.

mole-to-grams
Conversion Result
Moles
Molar Mass
Grams (mass)

Mole Conversion Formulas

Moles to Grams: grams = moles × molar mass (g/mol)

Grams to Moles: moles = grams ÷ molar mass (g/mol)

Avogadro\'s Number: 1 mol = 6.022 × 10²³ particles

Common Molar Masses (Reference)

Compound/ElementFormulaMolar Mass (g/mol)
WaterH₂O18
Sodium ChlorideNaCl58.5
GlucoseC₆H₁₂O₆180
Calcium HydroxideCa(OH)₂74
OxygenO₂32

Frequently Asked Questions

What is a mole in chemistry?

A mole is a unit for counting particles. 1 mole = 6.022 × 10²³ particles (atoms, molecules, ions). Avogadro's number. Used to connect macroscopic (grams) to atomic scale.

What is molar mass?

Mass of one mole of substance in g/mol. For elements: atomic mass from periodic table. For compounds: sum atomic masses of all atoms. Example: H₂O = 2(1) + 16 = 18 g/mol.

How do I convert moles to grams?

Multiply moles by molar mass: grams = moles × molar mass (g/mol). Example: 2 mol H₂O × 18 g/mol = 36 g.

How do I convert grams to moles?

Divide grams by molar mass: moles = grams ÷ molar mass (g/mol). Example: 36 g H₂O ÷ 18 g/mol = 2 mol.

How do I find molar mass?

Look up atomic masses on periodic table. For each element, multiply atomic mass by # of atoms. Sum all. Example: NaCl = 23 + 35.5 = 58.5 g/mol.

Why is mole-to-gram conversion important?

Stoichiometry: calculating reactants/products in reactions. Labs: measuring chemicals by mass, not particles. Balancing equations requires mole ratios.

What is Avogadro's number?

6.022 × 10²³ particles per mole. Defined value. Links atomic scale to macroscopic scale. Allows counting trillions of atoms by weighing grams.

Can I use molar mass for any substance?

Yes, for molecular compounds, ionic compounds, elements. Molar mass = average atomic mass × number of atoms. Works for solids, liquids, gases.

How do subscripts in formulas affect molar mass?

Subscripts show number of atoms. Ca(OH)₂: Ca (40) + 2×O (16) + 2×H (1) = 74 g/mol. Higher subscripts = higher molar mass.

What is the relationship between moles, grams, and particles?

moles = grams ÷ molar mass. particles = moles × Avogadro's number. These three conversions solve most chemistry stoichiometry.

Why do we use moles instead of counting atoms directly?

Atoms are too small to count individually. Moles provide a practical unit bridging atomic and laboratory scales. Makes calculations manageable.

What are common mistakes in mole-gram conversion?

Forgetting subscripts in molar mass. Using wrong atomic masses. Not converting units. Confusing molarity (mol/L) with molar mass (g/mol).