Mass of 1.5 mole electron is

Mass of 1.5 mole of electron is 0.8229 mg

mass of electron = 9.11 * 10^-31 kg

mass of 1 mole of any substance ( Avagadro number ) = 6.022 * 10^23 /mol

1.5 moles of electron  = 1.5 * 6.022 * 10^23 = 9.033 * 10^23 /mol

mass of 1.5 mole of electron = 9.033 * 10^23 * 9.11 * 10^-31

mass of 1.5 mole of electron = 8.229 * 10^-7 kg

mass of 1.5 mole of electron = 8.229 * 10^-4 g

mass of 1.5 mole of electron = 0.8229 mg

Hope it helps

the answer for sodium is 0.186

the answer for rubidium is 0.251