SC/250 SC250 SC 250 UNIT 8 QUIZ

Question 1.

Question :

If you plotted the number of neutrons against the number of protons of all atoms listed in the periodic table of the elements, what would you discover?

Student Answer:

 All chemical elements have multiple isotopes.

 Approximately 2,000 isotopes have been identified.

 The number of protons nearly equals the number of neutrons for the lighter elements.

 Heavier elements tend to have more neutrons than protons.

 All of these are correct.

Question 2.

Question :

A particular isotope has a half-life of 10 minutes. If we start with 2,000 atoms now, in a half hour we will have how many atoms converted into something different?

Student Answer:

 2,000 atoms

 1,750 atoms

 500 atoms

 250 atoms

 125 atoms

Question 3.

Question :

Which of the following statements is a characteristic of environmental radioactivity?

Student Answer:

 Much of the Earth's interior heat comes from alpha decay.

 There was no environmental radioactivity before the discovery of nuclear energy by humans.

 All elements have both radioactive and stable isotopes.

 Radon atoms will sink in water.

 Much of Earth's interior heat comes from beta decay.

Question 4.

Question :

If an atom emits two protons and two neutrons, the atom has:

Student Answer:

 created a daughter nucleus from the parent nucleus.

 emitted an alpha particle.

 changed the mass and chemical identity of the atom.

 produced a small amount of helium.

 all of these are correct.

Question 5.

Question :

When we say that radioactivity is nature's "philosopher's stone," we mean that:

Student Answer:

 radioactivity was discovered by Plato.

 the number of neutrons in a radioactive nucleus can change.

 radioactivity can change the number of protons in a given nucleus.

 electron spin varies in a radioactive atom.

 any atom that undergoes radioactive decay eventually becomes an atom of lead.

Question 6.

Question :

Beta decay results in the emission of __________ from the nucleus of an atom.

Student Answer:

 a positron

 an electron

 a beta particle

 all of the above.

 none of the above.

Question 7.

Question :

Atoms are mostly comprised of:

Student Answer:

 mass times the speed of light.

 mass times the speed of light squared.

 mass divided by the speed of light, then squared.

 mass squared times velocity.

 none of the above.

Question 8.

Question :

What is the ITER project?

Student Answer:

 an attempt to produce electricity using fission.

 a group trying to stop the building of nuclear power plants.

 a project to produce electricity form clean coal.

 a new process to dispose of nuclear waste.

 a project to produce electricity using fusion.

Question 9.

Question :

The amount of energy that is estimated to be contained in the nucleus of a grain of sand would:

Student Answer:

 provide a year's worth of energy for the United States.

 equal the gasoline energy needed for a 20 mile trip.

 equal a dump-truck load of coal.

 be the same as year's hydroelectric energy output of Niagara Falls.

 provide a year's worth of energy for a person in the United States.

Question 10.

Question :

Which of the following is true about radioactive decay?

Student Answer:

 Once a nucleus begins to decay it is totally turned into energy.

 A helium proton was the first particle identified as a product of radioactive decay.

 Gamma decay depends on chemical reactions.

 Alpha decay results in one less neutron and one more proton.

 After beta decay, the number of protons in a nucleus is unchanged.