Mass-to-charge ratio
= Mass-to-charge ratio
{title2=$m/q$}
{wiki}
The ratio of an <ion>'s <mass> to its <electric charge>; in <SI> it has units $\mathrm{kg/C}$. A convenient numerical <mass spectrum> coordinate is $x=(m/\mathrm u)/z$, with $q=ze$ and positive integer $z$ here. This $x$ is <dimensionless>. Doubling $z$ at fixed <mass> halves $x$, so the <electric charge> state must be identified before assigning an <isotope>.