The Journey of the Atom

What was the significance of the article published in March 1940?

• It described the first successful nuclear fission experiment.

• It explained the law of conservation of mass.

• It detailed the possibility of constructing a super bomb using atomic energy.

• It introduced the concept of the atom.

Who first proposed the idea of the atom in ancient times?

• Democritus

• Socrates

• Plato

• Aristotle

What does the law of conservation of mass state?

• Mass is created during a chemical reaction.

• Mass is destroyed during a chemical reaction.

• The total mass of the reactants is greater than the total mass of the products.

• The total mass of the products is equal to the total mass of the reactants.

What was John Dalton's major contribution to chemistry?

• He discovered the neutron.

• He proposed the law of definite proportions.

• He developed the atomic theory.

• He discovered the electron.

What did J.J. Thomson discover in 1897?

• The proton

• The neutron

• The electron

• The atomic nucleus

What was the Plum Pudding model?

• A model where electrons orbit the nucleus in fixed paths.

• A model where electrons are embedded in a positively charged matrix.

• A model where the nucleus is made up of protons and neutrons.

• A model where atoms are indivisible particles.

What did Rutherford's gold foil experiment demonstrate?

• Atoms are indivisible.

• Atoms are made up of indivisible particles.

• Electrons are embedded in a positively charged matrix.

• Atoms have a small, dense, positively charged nucleus.

What was the major flaw in Rutherford's nuclear model?

• It didn't account for the existence of neutrons.

• It couldn't explain the absorption spectra of elements.

• It proposed that atoms are indivisible.

• It suggested that electrons are stationary.

What did Bohr's model of the atom introduce?

• The idea of quantized electron orbits.

• The law of conservation of mass.

• The concept of isotopes.

• The discovery of the neutron.

What are isotopes?

• Atoms with the same number of protons and neutrons.

• Atoms with the same number of neutrons but different numbers of protons.

• Atoms with different numbers of protons and neutrons.

• Atoms with the same number of protons but different numbers of neutrons.