At one time it was believed that an atom’s mass is distributed evenly throughout the atom’s volume. When $\alpha$-particles are aimed at a sheet of gold foil, the observations caused scientists to conclude instead that almost all the mass of the gold atom is concentrated at a single point within the atom. Which effect could occur only if almost all the mass of the gold atom is concentrated at a point?
- Aa few $\alpha$-particles bounce back
- Bmost $\alpha$-particles are only slightly deflected
- Csome $\alpha$-particles pass through without any deflection
- Dsome $\alpha$-particles are absorbed