Helium is the lightest noble gas and the second most abun-dant element (after hydrogen) in the universe.(a) The radius of a helium atom is 3.1x10^-11m; the radius of itsnucleus is 2.5x10^-15m. What fractionof the spherical atomicvolume is occupied by the nucleus (V of a sphere =4/3*πr³ The mass of a helium-4 atom is 6.64648x10^-24g, and eachof its two electrons has a mass of 9.10939x10^-28g. What frac-tion of this atom’s mass is contributed by its nucleus?

Helium is the lightest noble gas and the second most abun-dant element (after hydrogen) in the universe.(a) The radius of a helium atom is 3.1x10^-11m; the radius of itsnucleus is 2.5x10^-15m. What fractionof the spherical atomicvolume is occupied by the nucleus (V of a sphere =4/3*πr³ The mass of a helium-4 atom is 6.64648x10^-24g, and eachof its two electrons has a mass of 9.10939x10^-28g. What frac-tion of this atom’s mass is contributed by its nucleus?