use-molar-mass

Surface

Item	Purpose
`MolarMass`	Positive finite molar mass value with a display unit
`MolarMassUnit`	Supported molar-mass units, currently `g/mol` and `kg/mol`
`AtomicMassEntry`	Validated element symbol and atomic mass pair
`AtomicMassLookup`	Caller-controlled lookup table for formula calculations
`MolarMassCalculation`	Formula plus lookup calculation helper
`FormulaMolarMass`	Calculated molar mass with per-element contributions
`ElementMassContribution`	Atomic mass, count, and contribution for one element

Example

use std::error::Error;

use use_chemical_formula::ChemicalFormula;
use use_molar_mass::{AtomicMassEntry, AtomicMassLookup, MolarMassCalculation};

fn main() -> Result<(), Box<dyn Error>> {
    let formula = ChemicalFormula::parse("H2O")?;
    let lookup = AtomicMassLookup::from_entries([
        AtomicMassEntry::new("H", 1.008)?,
        AtomicMassEntry::new("O", 15.999)?,
    ]);

    let calculation = MolarMassCalculation::new(formula, lookup);
    let water = calculation.calculate()?;

    assert_eq!(water.molar_mass().to_string(), "18.015 g/mol");
    assert_eq!(water.contributions().as_slice()[0].to_string(), "H: 2 × 1.008 = 2.016 g/mol");

    Ok(())
}

Standard atomic mass helper

Use with_standard_atomic_masses() when the existing RustUse atomic-mass table is the desired data source.

use std::error::Error;

use use_chemical_formula::ChemicalFormula;
use use_molar_mass::MolarMassCalculation;

fn main() -> Result<(), Box<dyn Error>> {
    let water = MolarMassCalculation::with_standard_atomic_masses(
        ChemicalFormula::parse("H2O")?,
    )?
    .calculate()?;

    assert!((water.molar_mass().value() - 18.015).abs() < 0.001);

    Ok(())
}

Scope

use-molar-mass calculates formula molar masses from element counts and atomic masses. It does not balance reactions, model isotopic abundance, fetch external reference data, or provide a general dimensional-analysis system.

Installation

[dependencies]
use-molar-mass = "0.1.0"