Atom cbse

What did Rutherford’s alpha particle experiment prove?

• 1. Electrons

• 1. Protons

• 1. Neutrons

• 1. Nucleus

Why was Rutherford’s atomic model unstable?

• 1. Electrons do not remain in orbit.

• 1. Nuclei will break down.

• 1. The nucleus repels electrons.

• 1. Orbiting electrons radiate energy.

Balmer series lies in which spectrum?

• 1. Ultraviolet

• 1. Visible

• 1. Infrared

• 1. Partially Visible

According to the classical theory, the circular path of the electrons is

• 1. Circular

• 1. Parabolic

• 1. Spiral

• 1. Straight line

Electrons in the atom are held to the nucleus by

• 1. Nuclear Force

• 1. Coulomb’s Force

• 1. Gravitational Force

• 1. Van Der Waal’s Force

The electrons of Rutherford’s model would be expected to lose energy because

• 1. They jump on the nucleus

• 1. They move randomly

• 1. Radiate electromagnetic waves

• 1. Escape from the atom

Who discovered the first spectral series?

• 1. Lyman

• 1. Balmer

• 1. Paschen

• 1. Pfund

Which of the following did Bohr use to explain his theory?

• 1. Quantization of angular momentum

• 1. Conservation of Quantum frequency

• 1. Conservation of Mass

• 1. Conservation of Linear Momentum

The significant result deduced from Rutherford’s scattering experiment is that

• 1. the whole of the positive charge is concentrated at the centre of an atom

• 1. there are neutrons inside the nucleus

• 1. α-particles are hydrogen nuclei

• 1. electrons are embedded in the atom

The first model of the atom was proposed by

• 1. Neils Bohr

• 1. Albert Einstein

• 1. J.J Thompson

• 1. Ernest Rutherford