Write 3 observations of Rutherford's gold experiment about the model of an
atom.
Answers
Rutherford concluded from the α-particle scattering experiment that:
(i) Most of the space inside the atom is empty because most of the α-particles passed through the gold foil without getting deflected.
(ii) Very few particles were deflected from their path, indicating that the positive charge of the atom occupies very little space.
(iii) A very small fraction of α-particles were deflected by very large angles, indicating that all the positive charge and mass of the gold atom were concentrated in a very small volume within the atom.
On the basis of his experiment,
Rutherford put forward the nuclear model of an atom, which had the following features:
(i) There is a positively charged center in an atom called the nucleus. Nearly all the mass of an atom resides in the nucleus.
(ii) The electrons revolve around the nucleus in well-defined orbits.
(iii) The size of the nucleus is very small as compared to the size of the atom. Rutherford's alpha particle scattering experiment shows the presence of nucleus in the atom.
It also gives the following important information about the nucleus of an atom :
(i) The nucleus of an atom is positively charged.
(ii) The nucleus of an atom is very dense and hard.
(iii) The nucleus of an atom is very small as compared to the size of the atom as a whole.
Rutherford model of the atom is also called Nuclear model of the atom.