Physics HW 12

d. neutrons

Different isotopes of an element have different numbers of A. protons. B. hadrons. C. photons. D. neutrons. E. none of these

c. ejected neutrons

In the fissioning of uranium, a chain reaction is caused by A. the enormous energy release. B. the kinetic energy of the decay products. C. ejected neutrons. D. the conversion of mass to energy. E. none of these

c. protons and neutrons

The atomic mass number of an element is approximately the same as the number of its A. protons. B. neutrons. C. protons and neutrons. D. electrons. E. protons and electrons.

a. protons

The atomic number of an element is the same as the number of its A. protons. B. neutrons. C. nucleons. D. neither of these

c. one-quarter

The half-life of an isotope is one day. At the end of two days the amount that remains is A. none. B. one-half. C. one-quarter. D. one-eighth. E. none of these

d. one-eighth

The half-life on an isotope is one day. At the end of three days, how much of the isotope remains? A. none B. one-half C. one-quarter D. one-eighth E. none of these

c. gamma

What type of radiation is most dangerous to humans? A. alpha B. beta C. gamma D. neutron

c. Poland

What was Marie Curie's native country? A. France B. Germany C. Poland D. Russia E. America

c. 90

When radium (atomic number = 88) emits an alpha particle, the resulting nucleus has atomic number A. 86. B. 88. C. 90. D. 92. E. none of these

d. 91

When thorium (atomic number = 90) emits a beta particle, the resulting nucleus has atomic number A. 88. B. 89. C. 90. D. 91. E. 92.

e. steel manufacturing

Which of the following is NOT an application of radioactivity? A. food safety B. medical testing C. smoke detectors D. carbon dating E. steel manufacturing

c. gamma rays

Which radiation has no electric charge associated with it? A. alpha rays B. beta rays C. gamma rays D. all of these E. none of these

90

A U-235 atom decays by alpha emission. What is the atomic number of the element after decay?

d. Geiger counter

A device that is used primarily to detect nuclear radiation is a A. synchrotron. B. linear accelerator. C. cyclotron. D. Geiger counter. E. All of the above choices are correct.

?

A particular nucleus has an atomic number of 17 and an atomic mass of 64 amu. How many neutrons are in the nucleus?

?

A radioactive nucleus with atomic number 87 decays by emitting an electron. What is the nucleus's atomic number after it decays?

a. beta particle

An element will decay to an element with higher atomic number in the periodic table if it emits A. a beta particle. B. a gamma ray. C. a proton. D. an alpha particle. E. none of these

61

Approximately how many neutrons are in Ag-108?

a. organic material

Carbon dating requires that the object being tested contain A. organic material. B. inorganic material. C. charcoal. D. sugar molecules. E. none of these

d. number of nuclei

The rate of radioactive decay is proportional to the A. atomic number. B. atomic mass. C. number of neutrons. D. number of nuclei. E. number of electrons.