muon molar mass (chemistry)

 The muon is an elementary particle similar to the electron, with unitary negative electric charge (−1) and a spin of 1⁄2, but with much more mass.  
In chemistry, the molar mass  M  is a physical property. It is defined as the mass of a given substance (chemical element or chemical compound) divided by its amount of substance. The base SI unit for molar mass is kg/mol.  The molar mass of a substance is the mass of 1 mol of the substance.