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

e/m value is the charge/mass value.

For electron:

$\mathrm{e}/\mathrm{m}=\frac{1.6\times {10}^{-19}}{9.1\times {10}^{-31}}=1.76\times {10}^{11}$

For proton,

$\mathrm{e}/\mathrm{m}=\frac{1.6\times {10}^{-19}}{1.6\times {10}^{-27}}=1\times {10}^8$

For neutron, there is no charge. Hence, e/m value is zero.

For alpha-particle,

$\mathrm{e}/\mathrm{m}=\frac{2}{4}=0.5$

The increasing trend of e/m values is:

n,$\alpha ,$p,e