Equivalent Mass of Metal is the no. of parts by mass of element which can displace/combine with 1.008 parts by mass of hydrogen or 8 parts by mass of oxygen or 35.5 parts by mass of chlorine. And is denoted by E.MMetal. Equivalent Mass of Metal is usually measured using the Gram for Weight. Note that the value of Equivalent Mass of Metal is always negative. Typically, the value of Equivalent Mass of Metal is greater than -1.