Nuclear ChemistryReview

An unstable nucleus ____.

a. increases its nuclear mass by fissionb. increases its half-lifec. emits energy when it decaysd. expels all of its protons

Ionizing radiation that consists of helium nuclei is ____.

a. Alpha Radiation

b. Beta Radiation

c. Gamma Radiation

d. Neutron Radiation

Which type of ionizing radiation can be blocked by clothing?

a. Alpha Radiation

b. Beta Radiation

c. Gamma Radiation

d. Neutron Radiation

If an isotope decays by the process of beta emission, ____.a. the mass number changesb. the atomic number changesc. protons are given offd. Both a & b

What particle does argon-39 emit when it decays to potassium-39?

a. neutronb.electronc. protond.alpha particle

To what element does polonium-208 decay when it emits an alpha particle?

84

208Po 2

4 82

204 Pba. Lead-204

b. Lead-207

c. Radon-212

d. Radon-222

Controlled nuclear chain reactions ____.a. take place in nuclear reactorsb. are always fusion reactionsc. never produce radioactive by-productsd. are characteristic of atomic bombs

Nuclear fusion ____.

a. takes place in the sunb. occurs at low temperaturesc. can be controlled in the laboratoryd. does not exist

A reaction that results in the combining of smaller atomic nuclei is called _______.a. Fissionb. Fusionc. Bombardment by beta particlesd. A chemical reaction

What does increasing neutron absorption accomplish in a nuclear reactor?a. It speeds up the reactionb. It can make the reactor explodec. It slows down the reaction.d. Trick question, electrons are used in nuclear

reactors, not neutrons.

Complete the following nuclear reaction:

a. 231, 88b. 239, 94c. 238, 91d. 235, 90

?? 4 23192 2 ??U He Th

If the half-life of a radioactive material is 8 years, how many years will it take for one half of the original amount of material to decay?a. 4 years

b. 8 years

c. 16 years

d. Need more information

After 42 days, 2 g of phosphorus-32 has decayed to 0.25 g. What is the half-life of phosphorus-32?

a. 14 days

b. 21 days

c. 32 days

d. 10.5 days

The radioisotope radon-222 has a half-life of 3.8 days. How much of a 73.9g sample of radon-22 would be left after 22.8 days?

a. 1.1 gb. 3.8 gc. 18 gd. 2.3 g

If the half-life of sodium-24 is 15 hours, how much remains from a 10.0-g sample after 60.0 hours?

a. 160 g

b. 7.5 g

c. 1.5 g

d. 0.63 g

a. 14,000 yearsb. 11,460 yearsc. 5,730 yearsd. Need more information

The concentration of carbon-14 in a piece of wood from an ancient burial mound indicates that two half-lives of this radioisotope have passed. If the half-life for carbon-14 is 5730 years, approximately how many years ago did this sample of wood die?

A sample of sodium-25 has a rate constant of 2.94 yrs-1, how long would it take for a sample to decay from 3.00 g to 2.00 g?

a. 0.225 years

b. 0.225 hours

c. 0.138 years

d. 0.138 hours

Sulfur-34 has a half life of 13.9 hours. If a 15 g sample is left in a beaker for 24 hours, how much sulfur will remain?a. 7.5 gb. 4.5 gc. 5.6 gd. 3.8 g

How many neutrons are in an alpha particle?

a. 1

b. 2

c. 3

d. 4

What is the approximate ratio of neutrons to protons for stable atoms below atomic number 20?

a. 1

b. 2

c. 3

d. 4

What other particle(s) is involved when Radon-222 produces Polonium-218 and is it through bombardment or decay?

a. 2 neutrons; decay

b. 2 neutrons; bombardment

c. Alpha; decay

d. Alpha; bombardment