What is “heavy water” used in nuclear reactors? a) Water rich in minerals b) Ozonised water c) Water with heavy metal minerals d) Water containing heavy isotope of hydrogen Answer: d
Which of the following is not a radioactive element? a) Uranium b) Thorium c) Radium d) Cadmium Answer: d
Who discovered radioactivity in 1898? a) Henri Becquerel b) J.J. Thomson c) Marie Curie d) Pierre Curie Answer: a(Note: Becquerel discovered it in 1896, not 1898. Marie Curie made key discoveries in 1898.)
Why are radioactive samples stored in lead boxes? a) Because lead is heavy b) Because it is strong c) Because it absorbs radiation well d) Because it’s a poor conductor Answer: c
An endothermic reaction is one in which: a) Heat is released b) Heat is absorbed c) No heat change occurs d) None of the above Answer: b
Nuclear forces are: a) Charge-independent b) Spin-independent c) Charge-symmetric d) Long-range Answer: a
Which feature is typical of an exothermic reaction? a) Release of heat b) Absorption of heat c) No temperature change d) None of these Answer: a
Which is the lightest radioactive element? a) Deuterium b) Polonium c) Tritium d) Uranium Answer: c
What is commonly used as a coolant in nuclear reactors? a) Water b) Uranium c) Graphite d) Boron Answer: a
Which element does not occur naturally but can be made artificially? a) Thorium b) Radium c) Plutonium d) Uranium Answer: c
What is used as a control rod material in nuclear reactors? a) Sodium b) Uranium c) Graphite d) Boron Answer: d
Which of the following is a radioactive element? a) Cobalt b) Uranium c) Argon d) Chromium Answer: b
Radiocarbon dating is used to estimate the: a) Soil contamination b) Water content in fossils c) Age of fossils d) Quality of soil Answer: c
Radioactive elements emit: a) Radiowaves b) Infrared waves c) Ultraviolet waves d) Alpha, Beta, and Gamma radiations Answer: d
Which rays are essential for radiocarbon dating? a) UV rays b) IR rays c) Cosmic rays d) X-rays Answer: c
What caused radioactive pollution along Kerala’s coast? a) Plutonium b) Zinc c) Thorium d) Radium Answer: c
What technique uses radioactivity to determine the age of prehistoric materials? a) Radium dating b) Uranium dating c) Carbon dating d) Deuterium dating Answer: c
Which of the following elements is not naturally radioactive? a) Uranium b) Thorium c) Aluminium d) Polonium Answer: c
Curie point refers to the temperature at which: a) Matter becomes radioactive b) Metal loses magnetic properties c) Metal becomes a poor conductor d) Metal transmutes Answer: b
The instability of a nucleus is primarily due to: a) High electron-to-proton ratio b) High neutron-to-proton ratio c) Low electron-to-proton ratio d) Low neutron-to-electron ratio Answer: b
Which radioactive isotope is used in treating skin diseases? a) Lead b) Cobalt c) Phosphorus d) Iodine Answer: b
Which of the following nuclei is unstable? a) ⁵B¹⁰ b) ⁴Be¹⁰ c) ⁷N¹⁴ d) ⁸O¹⁶ Answer: b
