Molarity Calculator, Dilution and Stoichiometry
Free suite for chemical calculations: molarity (C = n/V), dilutions (C₁V₁ = C₂V₂) and stoichiometry mole-to-mole from balanced coefficients.
Configure
Formula: n = m / 1000 - C = n / V
Result
No results
Enter values and press the button to calculate.
Frequently Asked Questions
How is the molarity of a solution calculated?
Concentration (C) is the number of moles of solute per liter of solution. It's calculated as C = n/V, where n are moles (n = mass/mass molecular) and V is volume in liters. Example: 5.85 g of NaCl (MM=58.5 g/mol) in 500 mL → n=0.1 mol → C=0.2 M.
What is the dilution law C1V1 = C2V2?
The law of dilution states that the number of moles of solute remains constant before and after dilution: C1V1 = C2V2. Where C1 and V1 are the concentration and volume of the mother solution, C2 and V2 are those of the diluted final solution.
How is stoichiometry used to calculate product moles?
Molecular ratio between reactants and products is indicated by stoichiometric coefficients from the balanced equation. Formula: mol_product = mol_reagent × (product_coefficient / reagent_coefficient).
What is the difference between molarity (M) and molality (m)?
Concentration (M) is moles of solute per liter of solution - depends on temperature. Concentration (m) is moles per kg of solvent - temperature-independent, used for colligative properties. This calculator uses molality (mol/L).
How do you calculate the dilution factor in molecular biology?
Dilution factor is the ratio of C1 to C2. Example: Diluting 100 µL of stock 1M in 900 µL of buffer → Final volume = 1000 µL, C2 = 0.1 M → Factor 10× (1:10). This tool automatically calculates the dilution factor.
Does this calculator work for any concentration unit?
Yes, as long as the units are consistent. For molarity we use mol/L and grams. For dilutions and stoichiometry, formulas are agnostic: you can use µM, mM, µL, mL - the result will be in the same units as the input.
How is it used?
- Select calculation
Choose the correct sheet: Calculate molarity, dilution for C1V1 = C2V2, or stoichiometry for reactant and product ratios.
- Enter known values
Fill in fields with available data using indicated units. For dilutions, select which variable you want to calculate.
- Get the result
Click the button to calculate. The result is displayed with the main value and corresponding units for immediate verification.
Why is quantitative chemistry essential?
Concentration unit is the most commonly used size of concentration in biochemistry, molecular biology and pharmacology. It expresses how many moles of solute are present in a liter of solution and allows for comparison of experiments on different scales, from µL to industrial bioreactors.
Serial dilutions are the basis of every PCR, ELISA, and titration protocol. The law C₁V₁ = C₂V₂ derives from the conservation of mole number of solute: independent of temperature and pressure, it applies to ideal diluted solutions and typical micromolar concentrations in research laboratory settings.
Molecular stoichiometry is the tool used to quantify reagents and products in any balanced chemical reaction. In enzymatic processes and peptide synthesis, accurately calculating moles limits waste and increases yield without needing to recalibrate every time due to trial and error.
This suite collects the three most requested calculations into one tool, without recording: enter known values, obtain the result with pre-calculated dilution factor or molar ratio, and use the AI panel to interpret the data in the context of your experiment.
Calculations occur entirely in the browser: no data is sent to the server. Formulas implemented follow IUPAC definitions: n = m/MM, C = n/V, C₁V₁ = C₂V₂, mol_B = mol_A × (coeff_B/coeff_A).
Practical example
Scenario: Preparare 500 mL di soluzione 0,2 M di NaCl da polvere pura (MM = 58,44 g/mol), poi diluirla 1:10 per un saggio ELISA.
- Scheda Molarità - Inserisci: massa=5,844 g, MM=58,44 g/mol, V=0,5 L → risultato:
n = 0,1 mol,C = 0,2 M. - Scheda Diluizioni - Target C₂, inserisci: C₁=0,2 M, V₁=0,1 L, V₂=1,0 L → risultato:
C₂ = 0,02 M, fattore =10×. - Scheda Stechiometria - Calcola moli di CO₂ da 3 mol di glucosio in C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O: coeffA=1, coeffB=6 →
mol CO₂ = 18 mol. - Verify results with integrated AI panel to contextualize data in experimental protocol.
Vocabulary
- Concentration (M)
- Number of moles of solute per liter of solution [mol/L]. Symbol: C or [X]. It is the most common measure of concentration in analytical chemistry and molecular biology.
- Molar mass
- Mass of one mole of substance [g/mol]. Derived from the periodic table by summing the atomic masses of all atoms in the molecular formula. NaCl: 22.99 + 35.45 = 58.44 g/mol.
- Serial Dilation
- Progressive dilution sequence (e.g. 1:10 x n step) used to build calibration curves, test multiple concentrations of drug or prepare standard ELISA from a single concentrated stock.
- Dilution factor
- Concentration ratio C1/C2: indicates how much the concentration has been reduced. A factor of 10x (dilution 1:10) means the final concentration is one-tenth of the initial concentration.
- Stoichiometric coefficient
- Number of whole atoms before chemical formula in a balanced equation indicates the mole ratio between reactants and products.
- Mouth
- Units of mass per quantity of substance. One mole contains exactly 6.022 × 10²³ elementary entities (Avogadro's number, N_A). Connects atomic scale to macroscopic scale of grams measurable in the laboratory.
Do you need a custom analysis?
This tool is free and informative. For in-depth analysis with AI on-prem - private data, zero cloud - contact Federico.