Calculadora de Grama para Mol
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
n = m / M
About this calculator
The Grams to Moles Calculator converts the mass of a substance (in grams) to the amount of substance (in moles) using the provided molar mass. The fundamental relation is n = m / M, where n is the number of moles, m is the mass in grams, and M is the molar mass in g/mol. This tool is essential for stoichiometry, solution preparation, and everyday chemical calculations.
To use the calculator, enter the mass of the substance in grams and its molar mass. The result is the corresponding number of moles. For example, 36 grams of water (molar mass 18 g/mol) equals 2 moles. The calculator accepts decimal values and provides results with adjustable precision.
This conversion is used in laboratories, industries, and classrooms to relate mass and amount of particles. It is useful when preparing solutions of known concentration, calculating reactants in chemical reactions, or determining the amount of substance in a sample.
Cautions: verify the correct molar mass for the specific substance (including hydration if applicable). The calculator assumes constant molar mass and does not account for impurities. Use consistent units (grams and g/mol).
Frequently asked questions
What is molar mass and how do I find it?
Molar mass is the mass of one mole of a substance, expressed in g/mol. Find it on the periodic table by summing the atomic masses of the elements in the molecule.
Can I use the calculator for any substance?
Yes, as long as you know the correct molar mass. The calculator works for any chemical compound or element.
Is the result exact?
The result depends on the precision of the input values. The calculator uses standard rounding; you can adjust the number of decimal places.
How do I convert moles back to grams?
Use the inverse formula: mass = n × M. Multiply the number of moles by the molar mass.
Do I need to consider the purity of the substance?
The calculator assumes a pure substance. If there are impurities, the actual number of moles is lower. Adjust the mass input according to purity.