What is a Gold foil experiment?

Gold-foil experiment:

• The gold foil experiment was designed by Rutherford.
• In his experiment, the $\mathrm{\alpha }$ particles were made to come down on a thin gold foil.
• Alpha particles $\left(\mathrm{\alpha }\right)$ are made up of two protons and two neutrons tightly bound together which is identical to Helium-4.
• Many of the $\mathrm{\alpha }$ particles passed linearly through the gold foil.
• Some of the particles deviated at small angles.
• One out of every $12000$ particles appeared to bounce.

Conclusion of Rutherford's model of an atom:

• The space inside an atom is empty as most of the $\mathrm{\alpha }$ particles passed without deflection through the gold foil.
• The positive charge occupies a minimum space which indicates that very few particles were diverted from their path.
• A very small proportion of $\mathrm{\alpha }$ particles were diverted by ${180}^{\mathrm{o}}$.