Common Chemical Compounds and Reactions

BPCL's 'Pure for Sure' tagline emphasizes purity and quality assurance in petroleum products. This slogan reflects BPCL's commitment to delivering clean, reliable fuel to customers. Aqua Guard, ONGC, and IOCL are not associated with this specific purity-focused tagline.

Safety matches use potassium chlorate (not chloride), antimony sulfide, and glue on the match head. The striking surface contains red phosphorus. This combination ensures matches only ignite when struck against the prepared surface.

Hydrofluoric acid (HF) is used to etch glass because it reacts with silicon dioxide (SiO2), the main component of glass. This reaction produces silicon tetrafluoride and water, permanently marking the glass surface.

NaCl is the chemical formula for sodium chloride, commonly known as salt. It's composed of sodium (Na) and chlorine (Cl) ions. Vinegar is acetic acid, pepper is a spice blend, and sugar is sucrose.

A 'Gin Fizz' is created by adding carbonated water (club soda) to gin, lemon juice, and sugar. The carbonation creates the signature 'fizz'. Champagne would make it a 'Gin Rickey', lemonade would be too sweet, and tonic water creates a 'Gin and Tonic'.

Dry cell batteries (Leclanche cells) use a paste of ammonium chloride (NH4Cl) as the primary electrolyte, often with zinc chloride (ZnCl2) added to reduce polarization and improve performance. Sodium chloride, magnesium chloride, and calcium chloride are not used in standard dry cells - they would not provide the right electrochemical properties.

Calcium sulfate (CaSO4) when partially dehydrated forms Plaster of Paris, named after large gypsum deposits near Paris. This is a standard chemistry fact about common compounds and their commercial names. Coaltar is a coal byproduct, Rubidium is an element, and Bruster appears to be a fictional option.

Computer disks and storage media do not contain mercury. Fluorescent light bulbs contain small amounts of mercury vapor, traditional thermometers used mercury metal, and some blinking shoe lights use mercury switches. Mercury is toxic and its use is being phased out in many products.

The chemical formula for common salt (sodium chloride) is NaCl, consisting of one sodium and one chlorine atom. Na2Cl is incorrect, CoSa is not a valid formula, and NaOH is sodium hydroxide (lye).

The 2008 Chinese milk scandal involved melamine contamination in infant formula, affecting over 300,000 babies and causing 6 deaths. Melamine was fraudulently added to falsely increase protein readings in quality tests. The question cites 13,000 children which is likely outdated or incorrect.

Venom is the poisonous fluid that snakes inject through their fangs, used for hunting and defense. Alum is a chemical compound, ammonia is a gas, and sap is plant fluid - none are related to snake poison.

Green vitriol is ferrous sulphate (FeSO4·7H2O), not copper sulphate. Copper sulphate is blue vitriol. Galena correctly matches with lead sulphide (PbS), Plaster of Paris with calcium sulphate (CaSO4·½H2O), and Calomel with mercurous chloride (Hg2Cl2).

The fizz in soda water comes from dissolved carbon dioxide (CO2) gas under pressure. When the pressure is released (by opening the bottle), the CO2 comes out of solution, forming bubbles. Oxygen, hydrogen, and nitrogen are not used in carbonated beverages. The carbonation process was discovered by Joseph Priestley in 1767.

Common salt (sodium chloride) has the chemical formula NaCl. The proper notation uses capital Na for sodium and lowercase l for chlorine. Options A, C, and D use incorrect capitalization or wrong stoichiometry - the standard 1:1 ratio of sodium to chlorine gives NaCl, not NaCl2 or other variants.