How the mixing model works
A mixing model combines source amounts and source properties. The calculator first converts compatible quantities into one working basis. It then applies recovery values to each source. This produces an effective amount for every contribution.
The standard model uses a weighted concentration balance. Every source amount is multiplied by its concentration. Those products are added together. The sum is divided by the total effective amount.
Cf = Σ(QiCi) ÷ ΣQi
Target mode reverses this balance. It searches for two sources that surround the requested target. Their quantities are solved from total and component conservation. An impossible target produces a clear warning.
Supported applications
The calculator can model laboratory solutions, water treatment, fertilizer blends, fuels, paints, foods, and industrial batches. It also supports environmental end-member calculations. Isotope values use source fractions as weights. Thermal mode includes source heat capacities.
Density adjustment helps when mass and volume inputs appear together. A volume becomes mass by multiplying volume and density. A mass becomes volume by dividing mass by density. Consistent units remain essential for defensible results.
Uncertainty and sensitivity
Each source accepts quantity and concentration uncertainty. Independent errors are combined through analytical propagation. The report presents standard deviation and a confidence interval. It also ranks influential sources through local sensitivity derivatives.
Uncertainty results depend on the independence assumption. Correlated measurements need a covariance model. Treat the displayed interval as an engineering estimate. Validate critical work with appropriate laboratory or statistical methods.
Loss and reaction controls
Real mixtures may lose material after blending. Evaporation changes retained quantity. Decay, adsorption, and settling reduce retained components. Reaction yield represents incomplete conversion or recovery.
Loss values are applied after ideal source mixing. Quantity losses and component losses are tracked separately. This distinction can increase final concentration when solvent evaporates. It can decrease concentration when the measured component disappears.
How to use this calculator
- Select a calculation mode and mixing basis.
- Choose output units and numerical precision.
- Add each source with its amount and concentration.
- Enter density when mass-volume conversion is required.
- Add temperature and heat capacity for thermal mixing.
- Enter uncertainty values for interval estimates.
- Add component pairs for multi-component reporting.
- Apply realistic recovery and loss assumptions.
- Press calculate and inspect every warning.
- Export the report as CSV or PDF.
Important assumptions
The ideal model assumes complete and uniform mixing. It assumes additive source quantities unless losses are entered. Concentrations are converted through a ppm-equivalent representation. Dilute aqueous mass-per-volume units use the common approximation that one milligram per liter is near one part per million.
Molar conversions require a correct molar mass. Thermal calculations assume no heat escapes during mixing. Heat capacity remains constant across the selected temperature range. Isotope calculations use linear end-member mixing without fractionation.