Ch. 4 The Structure of the Atom

Multiple Choice

What did Democritus believe to be true about the atom?

• Democritus believed that atoms are indivisible particles that make up all matter.
• Democritus claimed that atoms are made of smaller particles.
• Democritus thought atoms could be created and destroyed.
• Democritus believed that atoms are large and visible particles.

Multiple Choice

What were Dalton's beliefs regarding the atom?

• Dalton thought all atoms are identical in mass and properties.
• Dalton claimed that atoms can combine in fractional ratios.
• Dalton believed that atoms are indivisible, unique to each element, and combine in whole-number ratios.
• Dalton believed that atoms can be created and destroyed.

Multiple Choice

What experiment was used to discover the electron?

• Photoelectric effect experiment by Albert Einstein
• Cathode ray experiment by J.J. Thomson
• Oil drop experiment by Robert Millikan
• Gold foil experiment by Ernest Rutherford

Multiple Choice

What experiment was used to discover the nucleus?

• Thomson's cathode ray experiment
• Millikan's oil drop experiment
• Bohr's atomic model experiment
• Rutherford's gold foil experiment

Multiple Choice

Who discovered protons and neutrons?

• Niels Bohr discovered protons; Albert Einstein discovered neutrons.
• Ernest Rutherford discovered protons; James Chadwick discovered neutrons.
• Marie Curie discovered protons; Max Planck discovered neutrons.
• Isaac Newton discovered protons; Richard Feynman discovered neutrons.

Multiple Choice

What does the atomic number tell us?

• The atomic number shows the chemical reactivity of an element.
• The atomic number represents the number of electrons in an atom.
• The atomic number tells us the number of protons in an atom.
• The atomic number indicates the mass of an atom.

Multiple Choice

What is the mass number equal to?

• The number of electrons in an atom.
• The total number of particles in an atom.
• The average weight of an atom.
• The sum of protons and neutrons in an atom's nucleus.

Multiple Choice

What are isotopes?

• Isotopes are elements with different numbers of protons and neutrons.
• Isotopes are the same as ions but with different charges.
• Isotopes are elements that have the same atomic mass but different chemical properties.
• Isotopes are variants of elements with the same number of protons but different numbers of neutrons.

Multiple Choice

How do mass number and atomic mass differ?

• Mass number includes electrons; atomic mass does not.
• Mass number is the average of all isotopes; atomic mass is the total of protons.
• Mass number is always a decimal; atomic mass is a whole number.
• Mass number is a whole number representing protons plus neutrons; atomic mass is a decimal reflecting the weighted average mass of isotopes.

Multiple Choice

What is alpha radiation?

• Alpha radiation is a type of non-ionizing radiation.
• Alpha radiation consists of beta particles, which are electrons.
• Alpha radiation is a type of ionizing radiation consisting of alpha particles, which are like helium nuclei.

• Alpha radiation is a form of electromagnetic radiation like X-rays.

Multiple Choice

What is beta radiation?

• Beta radiation is a form of electromagnetic radiation like X-rays.
• Beta radiation is a type of radiation that consists of alpha particles.
• Beta radiation is a type of radiation like electrons emitted during beta decay.

• Beta radiation is a type of radiation emitted during nuclear fusion.

Multiple Choice

What is gamma radiation?

• Gamma radiation is a type of particle radiation.
• Gamma radiation is low-energy sound waves.
• Gamma radiation is a form of chemical energy.
• Gamma radiation is high-energy electromagnetic radiation emitted during radioactive decay.