Question

Rutherford’s alpha particle scattering experiment established that

Answer 1

Alpha particles, also known as alpha rays or alpha radiation, are made up of two protons and two neutrons that are bound together to form a helium-$4$ nucleus-like particle. They're most commonly made during alpha decay, but they can also be made in other ways.

Complete answer:
Rutherford carried out an experiment in which he bombarded a thin sheet of gold with -particles and then observed the motion of the particles after they collided with the gold foil. Rutherford used a thin sheet of gold ($100$ nm thickness) to direct high-energy streams of -particles from a radioactive source. He wrapped a fluorescent zinc sulphide screen around the thin gold foil to analyse the deflection caused by the -particles. Certain findings made by Rutherford contradicted Thomson's atomic model.
Rutherford's findings led him to the following conclusions:
Since a large portion of the -particles bombarded at the gold sheet went through it without being deflected, the majority of the room in an atom is zero.
The gold sheet deflected some of the -particles at small angles, causing the positive charge in an atom to be unevenly distributed. In an atom, the positive charge is concentrated in a very small amount.
Just a few -particles were deflected out, implying that only a few -particles had approximately $180^\circ$ deflection angles. As a result, the positively charged particles in an atom occupy a very small amount in comparison to the overall volume of the atom.
Since only a small percentage of -particles is deflected by small angles and only a few by larger angles. Particles (positively charged) must reach a strong positively charged centre within the atom for this to happen (like charges repel each other). The nucleus is the name given to the atom's strong positively charged centre. As a result, it was determined that protons are not evenly distributed in an atom.

Note:
Rutherford's model depicted the atom as a small, dense, positively charged centre called a nucleus, in which nearly all of the mass is concentrated, and around which the light, negative constituents known as electrons circulate at a distance, similar to planets spinning around the Sun.