Heavy Water is so called because:

Correct option is D

Sol: The correct answer is (d) it uses Deuterium, a heavier isotopes of hydrogen, rather than Protium

Key points:

• ​Heavy water ($$D_2O$$) is called "heavy" because it contains deuterium, which is an isotope of hydrogen that has one neutron in addition to the usual proton found in hydrogen.
• This makes heavy water denser than normal water ($$H_2O$$​), which consists of protium (the most common hydrogen isotope with no neutrons).
• Heavy water is primarily used as a neutron moderator in nuclear reactors, but its name comes from the presence of deuterium.​
  

Information booster:

• It is used in nuclear reactors: Heavy water (D₂O) is indeed used as a neutron moderator in certain types of nuclear reactors, particularly in CANDU (Canadian Deuterium Uranium) reactors. The presence of deuterium allows heavy water to slow down neutrons effectively, which is crucial for sustaining nuclear fission reactions. This property makes heavy water an essential component in the operation of these reactors, as it helps maintain the chain reaction necessary for energy production.
•  It is used by heavy industries such as steel, chemicals, etc.: While heavy water itself is not typically used directly in heavy industries like steel production, it plays a significant role in nuclear power generation, which can indirectly support various industrial processes. Additionally, heavy water can be utilized in certain chemical reactions and research applications due to its unique isotopic properties, but its primary use remains in nuclear applications rather than in traditional heavy industries.
• Its density is three times that of normal water: This statement is incorrect. The density of heavy water is approximately 11% greaterthan that of normal water ($$H_2O$$​), not three times. The density of heavy water is around 1.107 g/mL, while normal water has a density of about 1 g/mL at room temperature. This increased density affects how objects behave in heavy water; for example, ice made from heavy water will sink in normal water.​