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How do the ways in which the mass and the charge of an atom are distributed differ?

Alpha particle tracks through gases and thin metal foils show few deflections. What does this tell us about the atom?

The following statements were thought to be correct in the nineteenth century. Which of them are now known to be incorrect? For those that are incorrect, indicate why the statement is wrong and modify it to be in accordance with modern views. (a) Energy can be neither created nor destroyed. (b) The acceleration of an object is proportional to the force applied to it and inversely proportional to its mass. (c) Atoms are indivisible and indestructible. (d) All atoms of a particular element are identical.

What are the similarities and differences among the isotopes of an element?

Find the number of neutrons and protons in each of the following nuclei: 63Li; 136C; 3115P; 9440Zr.

Find the number of neutrons and protons in each of the following nuclei: 188O; 2612Mg; 5726Fe; 10947Ag.

What limits the size of a nucleus?

How does the number of neutrons in a stable nucleus compare with the number of protons? Why is this?

(a) What is an alpha particle? A beta particle? A gamma ray? (b) How do they compare in general in ability to penetrate matter?

Can you think of why positrons emitted in beta decay generally have more energy than emitted electrons?

What happens to the atomic number and mass number of a nucleus when it emits an alpha particle?

What happens to the atomic number and mass number of a nucleus when it emits (a) an electron? (b) a positron? (c) a gamma ray?

(a) Under what circumstances does a nucleus emit an electron? A positron? (b) The oxygen nuclei 148O and 198O both undergo beta decay to become stable nuclei. Which would you expect to emit a positron and which an electron?

The carbon isotope 146C decays into the nitrogen isotope 147N. What kind of particle is emitted in the decay?

What happens to the half-life of a radionuclide as it decays?

If the half-life of a radionuclide is 1 month, is a sample of it completely decayed after 2 months?

Why is the 5626Fe nucleus the most stable (that is, the most difficult to break apart) nucleus?

Suppose the strong interaction did not exist, so there were no nuclear binding energies. If the early universe contained protons, neutrons, and electrons, what kind or kinds of matter would eventually fill the universe?

What property of atomic nuclei makes it possible for nuclear fission and fusion to give off energy?

What are the differences and similarities between fusion and fission?

What is the function of the moderator in a uranium-fueled nuclear reactor?

Why can ordinary uranium not be used to fuel a reactor cooled by ordinary water?

What fuel other than uranium can be used in a nuclear reactor?

(a) Could a gamma ray energetic enough to materalize into a proton-antiproton pair alternatively materialize into a neutron-antineutron pair? (b) Could a gamma ray energetic enough to materialize into a neutron-antineutron pair alternatively materialize into a proton-antiproton pair? Explain.

Discuss the similarities and differences between the neutron and the neutrino.

Why can neutrinos travel immense distances through matter whereas other elementary particles cannot?

Leptons and hadrons are the two classes of basic particle. How do they differ?

Which constituents of an atom consist of quarks and which do not?

No particle of fractional charge has yet been observed. If none is found in the future either, does this necessarily mean that the quark hypothesis is wrong?

The gravitational interaction alone governs the motions of the planets around the sun. Why are the other fundamental interactions not significant in planetary motion?

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