The scattering of a steam of positively charged when striking a thin film of gold confirms that

Rutherford gave an experiment called as gold foil experiment.

In his experiment, he took a gold foil and bombarded it with alpha particles which carry positive charge of +2 units. He at first thought that the particles will pass straight through the foil, but to his surprise, many of them passed through, some of them deflected their path and a few of them bounced back straight from their path.

From this observations, he concluded that in an atom, there exist a small positive charge that is present at the center. Because of this positive charge, the alpha particles deflected their path and some of them bounced straight back their path.

Thus, the correct statement is the positive charge in an atom must be located in a dense central mass.

Explanation:

In alpha scattering experiment following conclusion were made:

Explanation:

Geirger and Marsden (students of Rutherford) studied the scattering of alpha particles by gold foil on the advice of Rutherford and made the following conclusions :

1. mMost of the mass ( at least 99.95 % ) and all of the charge of an atom is concentrated in small region , that region is called as atomic nucleus .

2. Nucleus is positively charged and the nucleus occupies only about 10⁻¹² of the total volume of the atom or less.

3. In an atom there is a empty space which is maximum and revolve around the nucleus in the same way as the planets revolve around the sun.

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.