Topic 6 Quiz

Which one of these is the correct description of the stucture of an atom?
1. A blob of protons, neutrons, and electrons all mixed together.
2. Electrons in the nucleus surrounded by orbiting protons and neutrons.
3. Neutrons in the nucleus surrounded by orbiting protons and electrons.
4. Protons and neutrons in the nucleus, surrounded by orbiting electrons.
A negative ion is formed by:
1. Adding an electron to the atom
2. Adding a proton to the atom
3. Taking away a proton from the atom
4. Taking away an electron from the atom.
Isotopes are formed when:
1. there are different numbers of protons in the nucleus.
2. when there are different number of neutrons in the nucleus
3. when there are different number of electrons in the nucleus
4. only when both protons and neutrons are removed from the nucleus.
Which one of these will when a nucleus of an isotope is unstable?
1. The chemical reactions will be different
2. The element will melt.
3. The element is radioactive.
4. The element will attract extra electrons to make it stable.
Radioactive decay is random. This means that:
1. a regular pattern of decay will be observed, starting from the centre.
2. you cannot tell when an individual nucleus will decay.
3. you can only tell when a nucleus will decay after applying a very complicated formula.
4. no nuclei will decay.
Alpha decay is:
1. the emission of a helium nucleus
2. the emission of a helium atom
3. the emission of two protons
4. the emission of two neutrons
Beta decay is:
1. Long wavelength electromagnetic radiation
2. Short wavelength electromagnetic radiation
3. A high speed electron from the electron shells.
4. A high speed electron from the nucleus.
Which one of these processes causes beta decay?
1. An electron turns into a proton
2. A proton turns into a neutron ejecting an electron.
3. A neutron turns into a proton ejecting an electron.
4. The nucleus is so excited that an electron is spontaneously ejected - it "falls out of bed".
An alpha source can be used:
1. for measuring the thickness of sheet steel as it is made
2. in a smoke detector
3. as a radioactive tracer to help doctors diagnose an illness.
4. to investigate flaws (hole) in a large casting.
Which one of these happens when beta decay occurs?
1. The proton number goes up by 1 but the nucleon number stays the same.
2. The proton number goes down by 1 but the nucleon number stays the same.
3. The proton number goes down by 1 but the nucleon number goes up by 1.
4. The proton number goes up by 1 but the nucleon number goes down by 1.