## College Physics (7th Edition)

a). $6.4\times10^{-19}C$ b). 2 electrons
a). 1 alpha particle has 2 protons, 2 alpha particles will have 4 protons. The charge on 1 proton = $1.6\times10^{-19}C$ The charge on 4 protons will be = $4\times1.6\times10^{-19}C=6.4\times10^{-19}C$ b). 1 alpha particle has 2 protons. The atoms are electrically neutral and thus to neutralize the charge of 2 protons, 2 electrons will be needed. The alpha particle will have to accommodate 2 electrons to become a Helium atom.