Molar Mass

Test molarmass in your browser at

https://tntran09.github.io/molarmass

https://tonicdev.com/npm/molarmass

Install

npm install molarmass --save

Usage

molarmass(formula [, options]);

Parameters

formula : string, required

The chemical formula (case-sensitive)

Validity Matrix

	S	U	L	N	O	C	E
S		x			x
U		x	x	x	x	x	x
L		x	x	x	x	x	x
N		x		x	x	x	x
O		x			x
C		x		x	x	x	x
E

How to read this table

S: Beginning of the formula

U: Uppercase [A-Z]

L: Lowercase [a-z]

N: Number [0-9]

O: Open ( [

C: Close ) ]

E: end of the formula

Other allowed characters that are ignored: . - + = _ (space)

An 'x' in the table above at row R and column C means that a character of type R can be followed by a character of type C. For example, a number CAN be followed by an uppercase character, but NOT a lowercase character. A formula can ONLY begin with an uppercase character or open parentheses/bracket. A formula CANNOT end with an open parentheses/bracket

options : object, optional

Defaults to { }

Options

returnCompound : boolean

When set to true, returns an instance of the Compound class, which gives you access to the formula (string), molarMass (number), and elements (array) properties; when false, only the molar mass is returned as a number. Defaults to false.

The Compound's properties are read-only

Examples

var molarmass = require('molarmass');
console.log(molarmass('H')); // 1.00794
console.log(molarmass('OH')); // 17.00734
console.log(molarmass('H2')); // 2.01588
console.log(molarmass('(S8)')); // 256.52
console.log(molarmass('H2O')); // 18.01528
console.log(molarmass('C12H22O11')); // 342.29648
console.log(molarmass('H(CO)(CHOH)5H')); // 180.15588
console.log(molarmass('Na')); // 22.98977
console.log(molarmass('NaOH')); // 39.99711
console.log(molarmass('Cr2O7')); // 215.988
console.log(molarmass('Ca(OH)2')); // 74.09268
console.log(molarmass('Mg3(PO4)2')); // 262.857722
console.log(molarmass('((((Pt)7)5))')); // 6827.73
console.log(molarmass('(Fe2)O3')); // 159.6882
console.log(molarmass('(NH4)2Cr2O7')); // 252.06492

var c1 = molarmass('H2O', { returnCompound: true });
/*
  c1: Compound { formula: 'H2O', molarMass: 18.01528, elements: [Getter] }
  c1.elements: [
  {
    element: { name: 'Hydrogen', symbol: 'H', atomicNumber: 1, mass: 1.00794 },
    quantity: 2
  },
  {
    element: { name: 'Oxygen', symbol: 'O', atomicNumber: 8, mass: 15.9994 },
    quantity: 1
  }
]
*/

License

ISC License © Toan Tran