Silver nanoparticles of uniform, spherical size $0\mathrm{.}5\backslash$mu m are suspended in $1-$

proponal. Your task is to determine the concentration of monovalent salt necessary to be

added to suppress all EDL forces if the zeta potential is equal to $75$ mV$.$ The answer must

have at least two significant figures. Note the relative permittivity of $1-$proponal $(\backslash$epsi $)$ is

$20\mathrm{.}1,$ the Hamaker constant is $2\mathrm{.}0*10-20$J and the permittivity of free space $(\backslash$epsi $0)$ is $8\mathrm{.}854$x$10-$

$12$ C

$2$

$/$J$/$m