The increasing order for the values of e/m for electron, proton, neutron and alpha particle is

The increasing order for the values of e/m for electron, proton, neutron and alpha particle is  $\text{n, }\alpha \text{, p, e}$ .

$\frac{e}{m}$  value increase with decreasing mass and neutron having no charge.

So it has, least e/m value.