Question

Explain Rutherford alpha rays scattering experiment?

Answer 1

in 1911, Rutherford performed an experiment which is now for Rutherford alpha particle scattering experiment. In this experiment, a stream of high energy Alpha particles from radioactive source was allowed to Bombay duck in Gold foil. A circular flawless and steel coated with zinc sulphide was set up around the gold foil. A tiny flash of light called scintillation who was produced when animal for particle strike the zinc sulphide coated screen. The situation was observed with the help of movable microscope find the following observations were made from the Alpha particle scattering experiment

1. Most of the Alpha particles pass through the gold foil without any deflection

2. A small function of the Alpha particles deflected throw small angles
free.

3. Only a very few Alpha particle status 1 in 10000 after head on collision with the positive body return back suffering and deflection of 180 degrees

in the light of the above experimental results, Rutherford read the following conclusions

1.since most of the Alpha particles pass through the gold file without any deflection, the major part of space in an atom is empty

2 . since a few Alpha particles are deflected by small angles, the deflection is due to and normals repulsive force between positively charged Alpha particles and some positive body present within the atom and Alpha particles coming close to this positive body got affected by small angle. That positively charged body inside the Atom was named as nucleus

3. Some of a particle sphere deflected back at 180 degree after head on collision with this positive and Alpha particles are heavy particles the positively body must be heavy

4. since only are very few Alpha particles not deflected back, they have a positive body occupies a very small volume as compared to the total volume of the atom. The radius of the nucleus is around 10 to the power minus 13 cm while the atom is 10 to the power minus 8 sem that means if the radius of nucleus is 1 cm and the radius of atom would be one kilometre

5. of the Alpha particles have appreciation mass and they are deflected by the nucleus, the nucleus of an atom has an appreciable mass

Answer 2

★ Rutherford's α-ray scattering experiment:-

Rutherford bombarded a very thin piece of gold foil with a α particles as shown below.

★ Note:- Refer to the attachment for the diagram.

★ Observations:-

Form this experiment Rutherford found that,

→ Most of the a - particles passed through the gold foil undeflected.

→ A small fraction of the a – particle was l deflected by small angle.

→ A very few a - particles (<1 in 20,000) bounced back, that is, were deflected by nearly 180°.

★ Conclusions:-

On the basis of these observations, Rutherford drew the following conclusions regarding the structure of an atom.

1. As majority of the particles went through the foil undefelcted, indicates most of the space in an l atom is empty.

2. The scattering of a few particles through smaller angles and very few through longer angles from centre of the atom, indicates protons are present at the centre of atom.

3. The heavy positively charged central part of the atom is called as nucleus.

4. Nearly, all the mass of the atom is concentrated in the nucleus.