Chapter 20 Science Test

Front 1

The type of radioactive particle that can be stopped by a sheet of paper is the _____.

Back 1

alpha particle

Front 2

The most penetrating type of radiation is the _____.

Back 2

gamma ray

Front 3

One type of radioactive device that indicates the intensity of radiation with a clicking sound that increases in frequency as more radiation is present is a _____.

Back 3

Geiger counter

Front 4

A helium nucleus with two protons and two neutrons is called a _____.

Back 4

alpha particle

Front 5

When strong force is not sufficient to hold unstable nuclei together permanently, _____.

Back 5

the nuclei decay

Front 6

An instrument that detects radiation by means of a superheated liquid is a _____.

Back 6

bubble chamber

Front 7

Negatively charged particles emitted from a nucleus at a high speed are _____.

Back 7

beta particles

Front 8

The process by which nuclei having low masses are united to form nuclei with larger masses is _____.

Back 8

nuclear fusion

Front 9

The three types of nuclear radiation in increasing order of penetrating power are _____.

Back 9

alpha, beta, gamma

Front 10

The stability of an isotope nucleus depends on the _____.

Back 10

neutron-to-proton ratio

Front 11

Radioactive tracers are useful in ____.

Back 11

determining medical problems

Front 12

Both a fusion reactioln and a fission reaction _____.

Back 12

produce energy

Front 13

Neutrons released in a fission reaction can strike other nuclei and cause _____.

Back 13

a chain reaction

Front 14

What would a scientests most likely use carbon-14?

Back 14

to calculate the age of a piece of bone

Front 15

Thorium-234 has a half-life of 24 days. If you started with a 100-g sample of thorium-234, how much would remain after 48 days?

Back 15

25-g

Front 16

What element is most likely to be produced during nuclear fusion reaction in the Sun?

Back 16

helium-4

Front 17

If a source of radiation is placed near _____ cells, atoms in the cells can be ionized and can die or stop growing.

Back 17

cancer

Front 18

When the _____ in not large enough to hold a nucleus together tighly, the nucleus can become radioactive.

Back 18

strong force

Front 19

Materials that continue to glow in the dark after they have been exposed to light are said to be _____.

Back 19

phosphorescent

Front 20

The ratio of protons to neutrons in stable isotopes of the lighter elements tends to be approximately _____.

Back 20

1:1

Front 21

The most difficult radiation to block out is _____.

Back 21

gamma rays

Front 22

A particle released during the fission of uranium-235 is a _____.

Back 22

neutron

Front 23

If a neutron begins a nuclear chain reaction, then one product of that reaction must be _____.

Back 23

a neutron