MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which reaction represents natural nuclear decay?

a. H⁺ + OH^- --> H₂O

b. KClO₃ --> K⁺ + ClO₃

c. --> +

d. + --> +

Correct Answer: c

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Answer the following questions:

1. Over a period of time Uranium decays to Lead. What would account for this change?

a. Uranium is a metal

b. Lead has an atomic weight of 208.

c. Uranium decays through alpha emission

d. Uranium becomes excited and loses electrons

e. It is impossible for an element to change to another element.

2. Over a period of time Bismuth decays to Polonium. What would account for this change?

a. Bismuth is a metal

b. Polonium has an atomic mass of 84.

c. Bismuth decays through beta emission.

d. Bismuth ionizes and loses 2 protons

e. One element cannot change to another

Correct Answers:

1. c

2. c

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Answer the following questions:

1. The isotope Np-238 has a half-life of 2.0 days. If 84 grams are produced on Monday, how much will be remaining 4.0 days latter?

a. 18 grams.

b. 21 grams.

c. 35 grams.

d. 42 grams.

e. 84 grams.

2. The isotope Np‑238 has a half‑life of 2.0 days. If 96 grams are produced on Monday, how much will be remaining 6.0 days latter?

a. 8 grams.

b. 12 grams.

c. 24 grams.

d. 48 grams.

e. 96 grams.

Correct Answers:

1. b

2. b

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emission of radioactivity.
ILO:

The half-life of is 8.07 days. What fraction of a sample of remains after 24.21 days?

a. 1/2

b. 1/4

c. 1/8

d. 1/16

Correct Answer: c

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emission of radioactivity.
ILO:

The half-life of a radioactive substance is 2.5 minutes. What fraction of the original radioactive substance remains after 10 minutes?

a. 1/2

b. 1/4

c. 1/8

d. 1/16

Correct Answer: d

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

As a sample of the radioactive isotope decays, its half-life

a. decreases

b. increases

c. remains the same

Correct Answer: c

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

The diagram below represents radiation passing through an electric field

The arrow labeled A most likely represents

a. a positron

b. an electron

c. alpha radiation

d. gamma radiation

Correct Answer: b

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which type of radiation is most similar to high-energy x rays?

a. alpha

b. beta

c. neutron

d. gamma

Correct Answer: d

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which type of radiation has zero mass and zero charge?

a. alpha

b. beta

c. neutron

d. gamma

Correct Answer: d

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which type of radiation continues in a straight line when passed through an electric field?

a. alpha

b. beta

c. gamma

d. proton

Correct Answer: c

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which product of nuclear decay has mass but no charge?

a. alpha particles

b. neutrons

c. gamma rays

d. beta positrons

Correct Answer: b

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which type of emission has the highest penetrating power?

a. alpha

b. beta

c. positron

d. gamma

Correct Answer: d

MC	Chemistry	Standard: 02
Objective: 02. Evaluate how changes in the nucleus of an atom result in emissions of radioactivity.
ILO:

Which of the following reactions would you expect to produce the most energy?

a. H⁺ + OH^- H₂O (combination of a strong acid and a strong base)

b. 2H₂ + O₂ 2H₂O (combustion of hydrogen gas)

c. C₁₂H₂₄ + 18O₂ 12CO₂ +12H₂O (combustion of a large hydrocarbon)

d. ²H + ³H ⁴He + neutron (nuclear fusion of two hydrogen isotopes)

Correct Answer: d