Man-Made Materials — Set 4
Chemistry · मानव निर्मित सामग्री · Questions 31–40 of 50
Which polymer is commonly used for making lightweight carry bags and grocery bags?
Correct Answer: B. Polyethylene
Polyethylene, specifically the Low-Density (LDPE) type, is flexible and moisture-resistant. It is easy to process and very inexpensive to manufacture on a large scale. However, its widespread use has led to significant environmental pollution issues.
The monomer of Natural Rubber is?
Correct Answer: C. Isoprene
Isoprene is the organic compound that serves as the building block for natural rubber. Natural rubber is harvested as latex from the sap of rubber trees. Synthesis of rubber in labs often involves polymerization of similar small molecules.
Which of the following is a nitrogen-based fertilizer?
Correct Answer: B. Urea
Urea has the highest nitrogen content among all solid nitrogenous fertilizers in common use. It is produced by the reaction of liquid ammonia with carbon dioxide. Nitrogen is an essential nutrient for the vegetative growth of plants.
The chemical name of 'Bleaching Powder' is?
Correct Answer: B. Calcium Oxychloride
Calcium oxychloride is produced by the action of chlorine gas on dry slaked lime. It is used as a disinfectant for water and as a bleaching agent in the textile industry. It gradually loses its chlorine content when exposed to air.
Which gas is released when 'Baking Soda' reacts with vinegar?
Correct Answer: B. Carbon dioxide
Baking soda is a carbonate that reacts with the acetic acid in vinegar to produce gas bubbles. This rapid effervescence is a hallmark of the acid-base reaction between these two substances. The resulting gas is used in fire extinguishers and baking.
What is the primary use of 'Zeolites' in everyday chemistry?
Correct Answer: C. Water softening
Zeolites are porous minerals that act as ion exchangers to remove calcium and magnesium from hard water. They trap these 'hard' ions and release sodium ions in their place. This prevents the formation of scale in pipes and boilers.
Which synthetic polymer is used to make soft drink crates and plastic furniture?
Correct Answer: A. Polypropylene
Polypropylene is a rugged plastic that is resistant to chemical solvents and fatigue. It has a high melting point, which allows it to be used in products that require sterilization. It is also used for making ropes and automotive parts.
What is 'Galvanized Iron' coated with to prevent rusting?
Correct Answer: D. Zinc
Zinc acts as a sacrificial anode, corroding in place of the iron or steel it protects. Even if the coating is scratched, the zinc continues to protect the metal through galvanic action. This process significantly extends the life of iron structures.
Which acid is present in the lead-acid batteries used in cars?
Correct Answer: A. Sulfuric acid
Sulfuric acid serves as the electrolyte that allows ions to flow between the lead plates. During discharge, the acid reacts with the plates to produce lead sulfate. These batteries are rechargeable and can provide the high current needed to start an engine.
The material 'Cement' is primarily a mixture of silicates and aluminates of which metal?
Correct Answer: A. Calcium
Cement is made by heating a mixture of limestone (calcium carbonate) and clay. The resulting clinker is ground with a small amount of gypsum to control the setting time. It reacts with water to form a hard, stone-like mass.