Practice MCQ Questions and answers on Chemistry-GK

Seaweeds are among the most potent accumulators of iodine. Kelps of the Laminaria genus were identified as a major iodine source. Iodine is found at low concentrations throughout the ocean waters, many types of seaweed accumulate the element in very high levels.

Fluorine is the most electronegative element because electronegativity decreases on moving down the group. Hence, it gets reduced readily into F+ ion and is the strongest oxidising agent.

Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore, is less soluble in blood than nitrogen and prevents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.

Vulcanization is a chemical process for converting rubber or related polymers into more durable materials via the addition of sulfur or other equivalent “curatives” or “accelerators”. These additives modify the polymer by forming crosslinks (bridges) between individual polymer chains. Vulcanized materials are less sticky and have superior mechanical properties. A vast array of products are made with vulcanized rubber including tires, shoe soles, hoses, and hockey pucks. The process is named after Vulcan, Roman god of fire. Hard vulcanized rubber is sometimes sold under the brand names ebonite or vulcanite, and is used to make hard articles such as bowling balls and saxophone mouth pieces.

Chloride shift (also known as the Hamburger phenomenon or lineas phenomenon, named after Hartog Jakob Hamburger) is a process that occurs in a cardiovascular system and refers to the exchange of bicarbonate (HCO₃^-) and chloride (Cl^-) across the membrane of red blood cells (RBCs).

Neon is used in neon discharge lamps and advertising signs because the neon lights are visible from long distances. Since the light of neon signs has a better penetrating power through fog and mist, the neon signs are also used in beacon lights for the safety of air and sea navigation.

Radon due to its radioactive nature is used in treatment of cancer (Radiotherapy).

Inert gases are chemically unreactive.

Fluorine cannot form oxyacid because fluorine is more electronegative than oxygen. For oxygen to bind, it must be a positively charged ion.