Atomic Theory: MCQ1

Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons.

Johnstone Stoney is credited with naming the electron, a subatomic particle with a negative charge.

The Law of Conservation of Mass states that in a chemical reaction, atoms cannot be created or destroyed.

The Gold Foil experiment, conducted by Ernest Rutherford, involved firing alpha particles at a thin sheet of gold foil.

J.J. Thomson, through his cathode ray experiments, discovered that cathode rays are negatively charged particles.

Rutherford's alpha-particle scattering experiment revealed that a large number of alpha particles passed through the gold foil undeflected, suggesting a mostly empty space within atoms.

The mass number is the sum of the number of protons and neutrons in an atom's nucleus.

Neils Bohr developed the Bohr model of the atom, which describes electrons occupying quantized energy levels.

The relative atomic mass is the average mass of an atom of an element, relative to 1/12 the mass of an atom of carbon-12.

The Maltese Cross experiment, conducted by William Crookes, demonstrated the existence of cathode rays by observing a cross shape formed by the cathode rays.

Isotopes are atoms of the same element with the same number of protons but a different number of neutrons.

Robert Millikan's oil drop experiment determined the charge of an electron by observing the motion of charged oil droplets in an electric field.

The Bohr model of the atom proposes that electrons orbit the nucleus in specific energy levels.