Everyday Chemistry — Set 1
Chemistry · रोजमर्रा का रसायन · Questions 1–10 of 50
Which chemical is commonly used as a rodenticide to control rats and mice?
Correct Answer: C. Zinc Phosphide
Zinc Phosphide is highly toxic and serves as a common rodenticide. When ingested, it reacts with stomach acid to release poisonous phosphine gas. It is typically formulated as bait mixed with food grains.
What is the primary chemical component of common glass used in windows?
Correct Answer: C. Silicon Dioxide
Silicon dioxide is the main constituent of glass, making up about seventy percent of its composition. It is sourced from high-quality sand during the manufacturing process. Other chemicals are added to lower the melting point and improve durability.
Which chemical is used to give a yellow color to firework displays?
Correct Answer: D. Sodium salts
Sodium salts emit a very bright and distinct yellow light when heated in a flame. This occurs due to the excitation of electrons that release energy as visible light. In contrast, strontium is used for red and barium for green effects.
Which substance is added to LPG cylinders to detect gas leaks through its smell?
Correct Answer: A. Ethyl Mercaptan
Ethyl Mercaptan is a strong-smelling sulfur compound added to otherwise odorless fuel gases. It allows for the immediate detection of hazardous leaks in domestic kitchens. Only a very small concentration is required to produce a noticeable scent.
Which chemical is widely used as a permanent ink for marking fingers during elections?
Correct Answer: A. Silver Nitrate
Silver nitrate reacts with the skin's proteins to form a dark, water-insoluble stain. The mark cannot be easily washed off and only fades as skin cells naturally shed. It is light-sensitive and stored in dark bottles to prevent decomposition.
Which type of plastic is commonly used to manufacture non-stick cookware coatings?
Correct Answer: C. Polytetrafluoroethylene
Polytetrafluoroethylene, known as Teflon, is used for its exceptional non-stick properties. It is highly resistant to heat and chemically inert to most food substances. This polymer has one of the lowest coefficients of friction among solids.
Which chemical is primarily responsible for the 'hardness' of water?
Correct Answer: A. Calcium and Magnesium salts
Hard water contains high concentrations of dissolved calcium and magnesium ions. These ions prevent soap from lathering effectively by forming an insoluble scum. Boiling can sometimes remove temporary hardness caused by bicarbonates.
Which gas is used in the manufacture of vanaspati ghee from vegetable oils?
Correct Answer: C. Hydrogen
Hydrogen gas is bubbled through liquid vegetable oils in the presence of a nickel catalyst. This process, called hydrogenation, converts liquid unsaturated fats into solid saturated fats. It improves the shelf life and texture of the resulting fat product.
Which substance is commonly known as 'Milk of Magnesia' and used as an antacid?
Correct Answer: B. Magnesium Hydroxide
Magnesium hydroxide is an alkaline suspension used to neutralize excess stomach acid. It provides relief from heartburn and indigestion by increasing the pH of gastric juice. It is also used in some contexts as a mild laxative.
Which chemical is used as a dehydrating agent in desiccators to keep substances dry?
Correct Answer: D. Calcium Chloride
Anhydrous calcium chloride has a high affinity for water and absorbs moisture from the air. It is frequently used in laboratories and industrial packaging to prevent spoilage from humidity. When it absorbs enough water, it can actually dissolve into a liquid solution.