Chemymass NPM | npm.io

📝 Description

chemymass - Simple molar mass calculator. Calculates molar mass for any valid formula.

🔧 Installation

chemymass is easy to install, just do:

npm i chemymass

📕 Usage

chemymass from v2 is an ESM-only module - you are not able to import it with require().

If you cannot switch to ESM, please use v1 which remains compatible with CommonJS.

npm i chemymass@1

Ways to call the module from your program:

// Standard Long Mode - Get molar mass and element percentages.
import chemymass from "chemymass";

const formula = "H₂SO₄";
const precision = 3;
const units = "g/mol";
console.log(chemymass(formula, precision, units));

/* Output:
H₂SO₄:
2 H · 1.007825 = 2.016 (2.055% of mass)
1 S · 32.066 = 32.066 (32.694% of mass)
4 O · 15.9994 = 63.998 (65.251% of mass)
Total: 98.079 g/mol
*/

// Standard Short Mode - Get only molar mass.
import { short } from "chemymass";

const formula = "CuSO₄ · 5H₂O";
const precision = 7;
const units = "amu";
console.log(chemymass.short(formula, precision, units));

/* Output:
249.6848500 amu
*/

// Standard Verbal Mode - Get molar mass and element percentages from query.
import { verbal } from "chemymass";

const query = "Sugar";
const precision = 7;
const units = "Da";
chemymass.verbal(query, precision, units)
  .then(output => console.log(output));

/* Output:
Sugar - C₁₂H₂₂O₁₁:
12 C · 12.011 = 144.1320000 (42.1072251% of mass)
22 H · 1.007825 = 22.1721500 (6.4774492% of mass)
11 O · 15.9994 = 175.9934000 (51.4153256% of mass)
Total: 342.2975500 Da
*/

// Short Verbal Mode - Get only molar mass from query.
import { verbalShort } from "chemymass";

const query = "58-08-2";
const precision = 7;
const units = "u";
chemymass.verbalShort(query, precision, units)
  .then(output => console.log(output));

/* Output:
194.1918500 u
*/

// Standard Bulk Mode - Get molar mass and element percentages.
import { bulk } from "chemymass";

const formula = ["H₂SO₄", "H₂O", "CuSO₄"];
const precision = 3;
const units = "g/mol";
console.log(chemymass.bulk(formula, precision, units));

/* Output:
H₂SO₄:
1 S · 32.066 = 32.066 (32.694% of mass)
4 O · 15.9994 = 63.998 (65.251% of mass)
Total: 98.079 g/mol

H₂O:
2 H · 1.007825 = 2.016 (11.189% of mass)
1 O · 15.9994 = 15.999 (88.811% of mass)
Total: 18.015 g/mol

CuSO₄:
1 Cu · 63.546 = 63.546 (39.813% of mass)
1 S · 32.066 = 32.066 (20.090% of mass)
4 O · 15.9994 = 63.998 (40.096% of mass)
Total: 159.610 g/mol
*/

// Standard Short Mode - Get only molar mass.
import { bulkShort } from "chemymass";

const formula = ["H2SO4", "H2O", "CuSO4"];
const precision = 7;
const units = "amu";
console.log(chemymass.short(formula, precision, units));

/* Output:
98.0792500 amu
18.0150500 amu
159.6096000 amu
*/

📰 Notes

This module understands both normal numbers and subscripts. You don't have to specifically convert them.
Crystal Hydrates work without any modifications. Formulas can be with signs ·, × or *.
Verbal mode supported query types: Plain Text Name, CAS number, SMILES, IUPAC, FICTS identifier, Cactvs HASHISY, uuuuu identifier.
units is optional parameter which defaults to g/mol. Available options are g/mol (Grams per mole); kg/mol (Kilograms per mole); Da (Daltons); amu (Atomic mass unit); u (Same as amu) or "" (No units - just number).
(^2.0.3) Bulk options is now available. Just pass an array of formulas and all of them will be calculated.
precision is optional parameter which defaults to 3 if not passed to function.
Verbal mode is made possible by NIH NCI/CADD Group! Without their API, verbal mode probably wouldn't be a thing.