Chem test #3

What fraction of a Sr-90 sample remains unchanged after 87.3 years

1/8

Which balanced equation represents a spontaneous radioactive decay

14-6C-> 14-7N + 0- -1e

Which two radioisotopes have the same decay mode

37 CA and 53 FE

What mass of a 40 g sample of I-131 Will remain unchanged after 24 days

5 grams

Which radioisotope is used to determine the age of once living organisms

Carbon-14

Which isotope is used to treat cancer

Co-60

Which type of radiation has neither mass nor change

Gamma

Which radioisotope is used for diagnosing thyroid disorders?

I-131

Which phrase describes a risk of using the radio isotope Co-60 in treating cancer

Increased biological exposure

which net change occurs in both nuclear fission and nuclear fusion reactions

Mass is converted to energy

Which emission will be released from an unstable FE 53 nucleus

a positron

Which nuclear emission has the least penetrating power and the greatest ionizing ability

alpha particle

Which particle has the greatest mass

an alpha particle

The ratio of the mass of U-238 to the mass of Pb-206 can be used to

date geological formations

Which nuclear decay emission consists of energy only?

gamma radiation

Which statement best describes what happens in a fission reaction

heavy nuclei split into lighter nuclei

In a nuclear fusion reaction the mass of the products is

less than the mass of the reactants because some of the mass has been converted to energy

In which type of reaction do two lighter nuclei combine to form one heavier nucleus

nuclear fusion

One benefit of nuclear fission reactions is

production of energy

Which phrase describes a risk associated with producing energy in a nuclear power plant

production of wastes needing long-term storage

An unstable nucleus spontaneously releases a positron. This is an example of

radioactive decay

What evidence indicates that the nuclide of strontium-90 atoms are unstable

strontium-90 atoms spontaneously emit beta particles

A change in the nucleus of an atom that converts the atom from one element to another element is called

transmutation