Rusting of iron is prevented by galvanization, which is the coating of iron with:
A. Nickel
B. Zinc
C. Chromium
D. Tin
Answer: Option B
Solution (By JKExamLibrary)
Galvanization involves coating iron with zinc. Zinc acts as a sacrificial anode, corroding in preference to iron even if the coating is scratched. Tin plating (tin cans) only protects if the layer is intact.
Explanation:
Smelting involves heating the concentrated ore (often after roasting/calcination) with a reducing agent (like coke, CO) to reduce the metal oxide to the metal. For example, iron ore is smelted in a blast furnace. Roasting heats sulfide ores in air; calcination heats carbonate ores in absence of air; leaching dissolves out the metal.
Explanation:
Bleaching powder is chemically calcium oxychloride, with the formula CaOCl₂. It is produced by the action of chlorine gas on dry slaked lime (Ca(OH)₂). Option A is slaked lime, C is plaster of Paris, and D is washing soda. It is used for disinfecting water and bleaching textiles.
Explanation:
The element with atomic number 118 is Oganesson (Og). It is a synthetic element and a member of the noble gas group (Group 18). Ununennium is the temporary name for element 119, Tennessine is 117, and Nihonium is 113.
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