Regents Chemistry Test Preparation Practice Nuclear Reactions

Nuclei of U-238 atoms are*

(1) stable and spontaneously absorb alpha particles

(2) stable and spontaneously emit alpha particles

(3) unstable and spontaneously absorb alpha particles

(4) unstable and spontaneously emit alpha particles

Radiation is spontaneously emitted from hydrogen-3 nuclei, but radiation is not spontaneously emitted from hydrogen-1 nuclei or hydrogen-2 nuclei. Which hydrogen nuclei are stable?*

(1) nuclei of H-1 and H-2, only

(2) nuclei of H-1 and H-3, only

(3) nuclei of H-2 and H-3, only

(4) nuclei of H-1, H-2, and H-3

Which statement describes the stability of the nuclei of potassium atoms?*

(1) All potassium atoms have stable nuclei that spontaneously decay.

(2) All potassium atoms have unstable nuclei that do not spontaneously decay.

(3) Some potassium atoms have unstable nuclei that spontaneously decay.

(4) Some potassium atoms have unstable nuclei that do not spontaneously decay.

The stability of an isotope is related to its ratio of*

(1) neutrons to positrons

(2) neutrons to protons

(3) electrons to positrons

(4) electrons to protons

The stability of isotopes is related to the ratio of which particles in the atoms?*

(1) electrons and protons

(2) electrons and positrons

(3) neutrons and protons

(4) neutrons and positrons

What evidence indicates that the nuclei of strontium-90 atoms are unstable?*

(1) Strontium-90 electrons are in the excited state.

(2) Strontium-90 electrons are in the ground state.

(3) Strontium-90 atoms spontaneously absorb beta particles.

(4) Strontium-90 atoms spontaneously emit beta particles.

Which term identifies a type of nuclear reaction?*

(1) transmutation

(2) neutralization

(3) deposition

(4) reduction

Given the equation representing a reaction:

nuclear-chemistry, nuclear-reactions fig: chem82018-exam_g7.png

Which type of reaction is represented by this equation?*

(1) neutralization

(2) polymerization

(3) substitution

(4) transmutation

Given the balanced equation representing a nuclear reaction:

nuclear-chemistry, nuclear-energy, nuclear-chemistry, nuclear-reactions, nuclear-chemistry, nuclear-reactions fig: chem12012-exam_g12.png

Which phrase identifies and describes this reaction?*

(1) fission, mass converted to energy

(2) fission, energy converted to mass

(3) fusion, mass converted to energy

(4) fusion, energy converted to mass

Base your answers to questions 10 on the information below and on your knowledge of chemistry.

A nuclear reaction is represented by the equation below.

³₁H → ³₂He + ⁰_-1e

Explain why the equation represents a transmutation.*

Base your answers to questions 11 on the information below and on your knowledge of chemistry.

The isotope Rn-222 is produced by the decay of uranium in Earth’s crust. Some of this isotope leaks into basements of homes in areas where the ground is more porous. An atom of Rn-222 decays to an atom of Pb-206 through a series of steps as shown on the graph below.

periodic-table, identification-of-element fig: chem82017-exam_g23.png

Explain, in terms of elements, why the decay of Bi-210 is considered a transmutation.*

Base your answers to questions 12 on the information below and on your knowledge of chemistry.

Synthetic radioisotopes may be made by bombarding other nuclides with neutrons. The equations below represent a sequence of reactions converting stable iron–58 to cobalt–60, which is used in medical treatments.

periodic-table, identification-of-element fig: chem12023-exam_g34.png

State, in terms of elements, why equation 2 represents a transmutation reaction. [1]*

Base your answers to questions 13 on the information below.

Nuclear fission has been used to produce electricity. However, nuclear fusion for electricity production is still under development. The notations of some nuclides used in nuclear reactions are shown in the table below.

nuclear-chemistry, nuclear-reactions fig: chem62012-exam_g26.png

Compare the atomic masses of nuclides used in fusion to the atomic masses of nuclides used in fission.*

Base your answers to questions 14 on the information below and on your knowledge of chemistry.

One fission reaction for U-235 is represented by the balanced nuclear equation below.

nuclear-chemistry, nuclear-reactions fig: chem82015-exam_g9.png

Both radioisotopes produced by this fission reaction undergo beta decay. The half-life of Xe-140 is 13.6 seconds and the half-life of Sr-94 is 1.25 minutes.

Explain, in terms of both reactants and products, why the reaction represented by the nuclear equation is a fission reaction.*

Base your answers to questions 15 on the information below and on your knowledge of chemistry.

When uranium-235 nuclei are bombarded with neutrons, many different combinations of smaller nuclei can be produced. The production of neodymium-150 and germanium-81 in one of these reactions is represented by the equation below.

nuclear-chemistry, nuclear-reactions fig: chem82018-exam_g13.png

Germanium-81 and uranium-235 have different decay modes. Ge-81 emits beta particles and has a half-life of 7.6 seconds.

Explain, in terms of nuclides, why the reaction represented by the nuclear equation is a fission reaction.*