Common Chemical Compounds and Reactions

Washing soda is sodium carbonate decahydrate (Na2CO3·10H2O), used in washing and water softening. Calcium bicarbonate and calcium carbonate are different compounds. Sodium bicarbonate is baking soda, not washing soda.

Quartz is crystalline silicon dioxide (SiO2), the most abundant mineral in Earth's crust. It is piezoelectric, making it ideal for oscillating in quartz clocks. Germanium oxide and sodium silicate are chemically different substances.

Potassium nitrate (KNO3, also known as saltpeter) is widely used as a fertilizer because it provides both potassium and nitrogen - two essential nutrients for plant growth. While historically used in gunpowder and some medicines, its primary modern use is in agriculture. It is not used as salt (NaCl), in glass manufacturing, or as a primary pharmaceutical ingredient.

Sodium carbonate (washing soda, Na2CO3) removes permanent hardness by precipitating calcium and magnesium salts as insoluble carbonates. Lime (Ca(OH)2) only removes temporary hardness. Alum is used for water coagulation, not hardness removal, and potassium permanganate is a disinfectant/oxidizing agent.

Soda water is carbonated water created by dissolving carbon dioxide under pressure. The fizz comes from CO2 bubbles being released. While carbonic acid (H2CO3) forms when CO2 dissolves, the primary component added is carbon dioxide gas itself. Sulphuric and nitrous acids are not present in soda water.

Water consists of two hydrogen atoms bonded to one oxygen atom, giving it the chemical formula H2O. NaAlO2 is sodium aluminate, Al2O3 is aluminum oxide, and CaSiO3 is calcium silicate.

Washing soda is sodium carbonate (Na2CO3), specifically the decahydrate form used in cleaning and laundry. Sodium bicarbonate is baking soda, while calcium compounds (carbonate and bicarbonate) have different applications and are not called washing soda.

Quartz crystals, commonly used in quartz clocks and oscillators, are composed of silicon dioxide (SiO2). This crystalline mineral exhibits the piezoelectric effect, making it ideal for timekeeping applications.

Common table salt is sodium chloride (NaCl). Baking soda is sodium bicarbonate (NaHCO3), also known as sodium hydrogen carbonate. Option D is correct.

Concentrated sulfuric acid (H2SO4) is a powerful dehydrating agent because it has a high affinity for water, often removing hydrogen and oxygen atoms from compounds to form water.

Mercury is commonly found in fluorescent bulbs (as vapor), older thermometers (liquid metal), and specialized footwear like vintage 'LA Gear' light-up sneakers (mercury switches). Computer disks (floppy or hard drives) are primarily made of magnetic materials, plastics, and aluminum, and do not contain mercury.

Venom is the poisonous fluid that snakes and other venomous animals inject through fangs. Fumarin is not a standard biological term. Cyanide is a toxic chemical compound. Lead is a heavy metal, not a fluid.

Venom is the correct answer as it is the poisonous fluid that snakes inject through their fangs. Alum is a chemical compound, Ammonia is a gas, and Sap is plant fluid.

A SOAP message consists of three parts: the mandatory Envelope (root element), the optional Header (for metadata), and the mandatory Body (containing the actual message content). The Envelope encapsulates both Header and Body elements.