WorksheetsTopic 5
Total questions: 20
Worksheet time: 20mins
What is the nucleon number of a nuclide?
the number of neutrons in the nucleus
the number of protons in the nucleus
the number of protons minus the number of neutrons in the nucleus
the number of protons plus the number of neutrons in the nucleus
A thin sheet of paper is placed between a radioactive source and a radiation detector. The count rate falls to a very low reading.
From this result, which type of radiation is the source emitting?
α-particles
β-particles
γ-rays
X-rays
In 1986 the Chernobyl nuclear power station in Ukraine suffered a meltdown.
This caused background radiation in many countries, thousands of kilometres from Chernobyl, to increase.
What was transported in the atmosphere to these countries to cause this rise in background radiation?
α-particles
β-particles
γ-rays
radioactive isotopes
A nuclide of the element iron has the symbol shown.
56
Fe
26
What does a neutral atom of this nuclide contain?
Protons:26 Neutrons:30 Electrons:26
Protons:26 Neutrons:56 Electrons:30
Protons:30 Neutrons:26 Electrons:56
Protons:56 Neutrons:26 Electrons:30
Which statement about the nuclei of all atoms is correct?
They all contain electrons.
They are all always stable.
They all contain protons and electrons.
They all have a positive charge.
A radioactive isotope has a half-life of 120 minutes.
It emits radiation at a rate of 100 particles per second.
How long does it take for the rate of emission to fall to 25 particles per second?
30 minutes
45 minutes
90 minutes
240 minutes
Why should all radioactive materials be handled carefully?
They all make anything they touch radioactive.
They all catch fire very easily.
They all emit ionising radiation.
They all have long half-lives.
Which statement about the structure of an atom is correct?
Negative electrons surround a neutral nucleus.
Negative electrons surround a positive nucleus.
Positive electrons surround a neutral nucleus.
Positive electrons surround a negative nucleus.
What are isotopes of an element?
atoms of a different element with a different number of neutrons
atoms of a different element with a different number of protons
atoms of the same element with a different number of neutrons
atoms of the same element with a different number of protons
Four students are discussing ideas about radioactive decay.
Which student’s statement is correct?
When a β-particle is emitted, the nucleus remains unchanged.
When an α-particle is emitted, the nucleus changes to that of a different element.
When a γ-ray is emitted, the nucleus changes to that of a different element.
Stable nuclei are dangerous because they emit high levels of
γ-radiation.
An isotope of radon is radioactive. It decays by emitting an α-particle. What happens to the nucleus of a radon atom during the emission of the α-particle?
It becomes the nucleus of a different isotope of radon with fewer neutrons.
It becomes the nucleus of a different isotope of radon with more neutrons.
It becomes the nucleus of an element with a higher proton number.
It becomes the nucleus of an element with a lower proton number.
Why are some radioactive sources stored in boxes made from lead?
Lead absorbs emissions from the radioactive sources.
Lead decreases the half-life of radioactive sources.
Lead increases the half-life of radioactive sources.
Lead repels emissions from the radioactive sources.
Which type of radiation can be stopped by a sheet of Aluminium ?
α-particles only
α-particles and β-particles
α-particles and γ-rays
Χ-rays only
When measuring the emissions from a radioactive rock brought into the laboratory, a teacher mentions that background radiation must be taken into account.
What is this background radiation?
infra-red radiation from warm objects in the laboratory
infra-red radiation from the Sun
ionising radiation from the radioactive rock brought into the laboratory
ionising radiation in the laboratory when the radioactive rock is not present
Which statement about α-particles and β-particles is correct?
α-particles are less ionising than β-particles.
α-particles are more penetrating than β-particles
α-particles have greater mass than β-particles.
α-particles have the same charge as β-particles.
An explosion in a nuclear reactor spread the isotope caesium-137 across a large area.
Ninety years after the explosion, the quantity of caesium-137 present will be 12.5% of its original level.
What is the half-life of caesium-137?
11.25 years
22.5 years
30.0 years
45.0 years
Radioactive materials must be handled in a safe way.
What is not a safety procedure?
Monitor exposure time to radioactive materials.
Store radioactive materials in cardboard boxes.
Use tongs to pick up the radioactive source.
Wear protective clothing.
Three sources of background radiation are listed.
1. cosmic rays
2. medical X-rays
3. radioactive emissions from radon gas from the ground
Which of these sources are naturally occurring?
1 and 3 only
1 only
2 and 3 only
2 only
The nuclide notation for the isotope lithium-7 is
7
Li
3
How many neutrons are there in an atom of lithium-7?
3
4
7
10
Samples of four different radioactive isotopes all emit radiation at the same rate.
As time passes, the rates of emission decrease for all the samples.
Which sample of isotope has the greatest decrease in rate?
isotope:americium-241 . half-life:470 years
isotope:iodine-128 . half-life:25 minutes
isotope:thoron-220 . half-life:54.5 seconds
isotope:uranium-237 . half-life:6.75 days
