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Molar Mass & Molecular Weight Calculator

Calculate exact molar mass and element percentage composition for any chemical compound with laboratory precision.

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Molar Mass & Composition

Input a chemical formula to instantly calculate its molecular weight and see the percentage by mass of each constituent element.

Formula Conventions

Input formulas using standard IUPAC symbols. Support for parentheses is included (e.g., **(NH4)2SO4**). Ensure element symbols use correct case: **Ca** for Calcium, not **ca**.

Scientific Accuracy

Molar masses are derived from standardized IUPAC atomic weights. Percentages are calculated as (Total Atomic Mass of Element / Molecular Mass) × 100.

This science solver is useful for chemistry students, pharmaceutical researchers, and materials engineers performing stoichiometric conversions and formula analysis.

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The Significance of Molar Mass in Chemistry

In the science category, molar mass is defined as the mass of one mole of a substance (typically expressed in g/mol). This chemistry solver allows you to input any chemical formula—from simple oxides to complex organic polymers—and receive an instant breakdown of its molecular weight and the percentage composition of each constituent element.

Molar mass serves as the bridge between the microscopic world of atoms and the macroscopic world of laboratory measurements. It is the fundamental constant used to convert between mass (grams) and amount of substance (moles), which is the basis of all stoichiometric calculations.

How to Calculate Molecular Weight

This science solver utilizes the weighted average atomic masses of elements as defined by IUPAC. To get the best results:

  • Enter Chemical Formula: Use standard notation (e.g., H₂O, NaCl, C₆H₁₂O₆). Parentheses are supported for complex groups.
  • Review Results: The tool provides the total molar mass in g/mol.
  • Elemental Breakdown: An interactive table shows the mass contribution and percentage of each atom relative to the total.

Scientific Fundamentals

Molar Mass = Σ (Atomic Mass_i × Count_i)

Our chemistry solver incorporates the latest data from the Royal Society of Chemistry, ensuring that isotopic variances and standard atomic weights are accounted for with laboratory-grade precision.

Chemistry FAQ

What is Avogadro's Number?

One mole of any substance contains exactly 6.02214076 × 10²³ elementary entities. The molar mass is the mass of this specific number of particles.

Is molecular weight the same as molar mass?

In common lab parlance, yes. Technically, molecular weight is a dimensionless ratio, while molar mass has units of g/mol. The numerical values remain the same in most contexts.