Question 1

Gamma rays are not deflected by an electric field.

Accepted Answer

Gamma rays are neutral particles and do not carry any charge, hence, they are not deflected by an electric field.

Question 2

Gamma rays are high energy electrons.

Accepted Answer

Gamma rays are not electrons, they are a form of electromagnetic radiation with very high energy and short wavelength.

Question 3

For stable atoms of elements having low atomic numbers (≤ 20),the neutron-to-proton ratio is close to zero.

Accepted Answer

For stable atoms of elements having low atomic numbers (≤ 20), the neutron-to-proton ratio is usually close to 1:1 or sometimes slightly higher toward the neutron side.

Question 4

A radioisotope decays,producing an alpha particle and Th-234.The original radioisotope must have been an atom of ____.

Accepted Answer

When a radioisotope decays by emitting an alpha particle (which consists of 2 protons and 2 neutrons), the atomic number decreases by 2 and the mass number decreases by 4. Th-234 (Thorium-234) has an atomic number of 90 and a mass number of 234. Therefore, the original radioisotope must have had an atomic number of 92 (90 + 2) and a mass number of 238 (234 + 4), which corresponds to Uranium (U).

Question 5

Electron capture is the capture of an electron-usually a 1s electron-by the _________________.

Accepted Answer

The answer of Electron capture is the capture of an...

Question 6

A plot of the number of neutrons versus the number of protons in various isotopes produces a "belt of stability." Isotopes below the belt of stability (i.e.,with a smaller neutron-to-proton ratio)decay by beta particle emission.

Accepted Answer

The answer of A plot of the number of neutrons...

Question 7

Naturally occurring uranium contains approximately 1% U-235 and 99% U-238.Of these,the isotope that undergoes fission in a nuclear reactor is U-238.

Accepted Answer

The isotope that undergoes fission in a nuclear reactor is actually U-235, not U-238.

Question 8

A beta particle is a proton.

Accepted Answer

A beta particle is actually an electron or a positron, not a proton.

Question 9

A gamma particle has a charge of -1.

Accepted Answer

A gamma particle is actually a high-energy photon and has no electrical charge.

Question 10

The _______________ has the same mass as the electron,but bears a charge of +1.

Accepted Answer

The answer of The _______________ has the same mass as...

Question 11

A nuclear reaction's reaction rate is affected by temperature,pressure,and catalysts.

Accepted Answer

Nuclear reactions are governed by the properties of the atomic nuclei and the energy of the reacting particles, not by temperature, pressure, or catalysts, which primarily affect chemical reactions.

Question 12

A ___________ _____________ uses electric and magnetic fields to increase the kinetic energy of charged species so that a reaction will occur.

Accepted Answer

The answer of A ___________ _____________ uses electric and magnetic...

Question 13

An alpha particle is a helium atom.

Accepted Answer

An alpha particle is equivalent to a helium nucleus, consisting of 2 protons and 2 neutrons, but it lacks the electrons that would make it a complete helium atom.

Question 14

The difference between the mass of an atom and the sum of the masses of its protons,neutrons,and electrons is called the ___________ ___________.

Accepted Answer

The answer of The difference between the mass of an...

Question 15

The ___________ _________ ___________ is a quantitative measure of the nuclear stability of a nucleus,which is the energy required to break up a nucleus into its component protons and neutrons.

Accepted Answer

The answer of The ___________ _________ ___________ is a quantitative...

Question 16

Nuclear fusion is the combination of small nuclei into larger ones.

Accepted Answer

Nuclear fusion is the process where two or more atomic nuclei combine to form a single, more massive nucleus with the release of energy. It is the opposite process of nuclear fission where a larger nucleus splits into smaller ones.

Question 17

Alpha decay is not observed for isotopes of elements with atomic numbers less than 83.

Accepted Answer

Alpha decay can occur in isotopes of elements with atomic numbers less than 83, but it is more common and energetically favorable in heavier elements.

Question 18

All isotopes of elements with atomic numbers higher than 83 (Bi)are radioactive.

Accepted Answer

Isotopes of elements with atomic numbers higher than bismuth (Bi) have unstable nuclei and undergo radioactive decay.

Question 19

In a nuclear reaction elements are converted to other elements.

Accepted Answer

Nuclear reactions involve the splitting or combination of atomic nuclei, resulting in a change in the number of protons and/or neutrons, which leads to the formation of different elements. Therefore, elements can be converted to other elements in a nuclear reaction.

Question 20

Nuclear fission is the process in which a heavy nucleus (mass number > 200)divides to form smaller nuclei of intermediate mass and one or more protons.

Accepted Answer

Nuclear fission is the process in which a heavy nucleus splits into two or more smaller nuclei, along with the release of energy, neutrons, and often other particles. The mass number of the original nucleus does not need to be greater than 200, and the products are not limited to intermediate mass nuclei and protons.

Quiz 20: Nuclear Chemistry