Everyday Science one liner - Chemistry
1. Matter and States (Physical and Chemical Changes)
- What are the three classic fundamental physical states of matter? - Solid, Liquid, and Gas
- Which state of matter consists of superheated, highly ionized gas with free electrons? - Plasma
- In which natural celestial bodies is plasma predominantly found? - Stars and the Sun
- Which fifth state of matter is created by cooling a dilute gas close to absolute zero? - Bose-Einstein Condensate (BEC)
- Which two scientists formulated the theoretical framework for the BEC state of matter? - Satyendra Nath Bose and Albert Einstein
- In which state of matter are intermolecular forces of attraction strongest and particles fixed? - Solid
- In which state of matter do particles possess maximum kinetic energy and maximum randomness? - Gas
- What is the direct phase transition of a substance from solid directly to gas called? - Sublimation
- What is the direct phase transition from gas to solid without becoming a liquid called? - Deposition
- What is the temperature at which a liquid's vapor pressure equals atmospheric pressure? - Boiling Point
- What property of liquids causes spherical droplet formation to minimize surface area? - Surface Tension
- What is the internal resistance of a fluid to flow called? - Viscosity
- Which type of solid possesses a regular, repeating three-dimensional atomic arrangement? - Crystalline Solid
- What type of solid lacks a long-range repeating geometric atomic structure (e.g., Glass)? - Amorphous Solid
- What type of change occurs without forming any new chemical substance? - Physical Change
- What type of change results in the formation of chemically new substances with altered properties? - Chemical Change
- Is the melting of ice into water a physical or chemical change? - Physical Change
- Is the freezing of water into ice a physical or chemical change? - Physical Change
- Is the boiling or vaporization of water a physical or chemical change? - Physical Change
- Is dissolving sugar or common salt in water a physical or chemical change? - Physical Change
- Is the tearing or cutting of a sheet of paper a physical or chemical change? - Physical Change
- Is the glowing of a tungsten electric bulb filament a physical or chemical change? - Physical Change
- Is the condensation of steam into liquid water a physical or chemical change? - Physical Change
- Is the magnetization of an iron bar a physical or chemical change? - Physical Change
- Is the crushing of a dry chalk stick into fine powder a physical or chemical change? - Physical Change
- Is the sublimation of solid camphor or dry ice a physical or chemical change? - Physical Change
- Is the breaking of a glass tumbler a physical or chemical change? - Physical Change
- Is the stretching of a rubber band a physical or chemical change? - Physical Change
- Is the rusting of an iron nail in moist air a physical or chemical change? - Chemical Change
- Is the burning of wood, coal, or paper a physical or chemical change? - Chemical Change
- Is the curdling (souring) of milk into curd a physical or chemical change? - Chemical Change
- Is the digestion of food inside the human stomach a physical or chemical change? - Chemical Change
- Is cellular respiration in living organisms a physical or chemical change? - Chemical Change
- Is the photosynthesis process in green plant leaves a physical or chemical change? - Chemical Change
- Is the ripening of raw green fruits a physical or chemical change? - Chemical Change
- Is the explosion of firecrackers a physical or chemical change? - Chemical Change
- Is the cooking of food or baking of bread a physical or chemical change? - Chemical Change
- Is the fermentation of sugarcane juice into ethanol a physical or chemical change? - Chemical Change
- Is the burning of an LPG cooking fuel flame a physical or chemical change? - Chemical Change
- Is the tarnishing of a silver spoon when exposed to air a physical or chemical change? - Chemical Change
- What type of change is the burning of a wax candle? - Both (Melting of wax is physical, burning of wax is chemical)
- What is the spontaneous intermingling of particles of two different substances called? - Diffusion
- In which state of matter does diffusion occur at the fastest rate? - Gaseous State
- What temperature scale has absolute zero ($0\text{ K}$) as its lowest theoretical starting point? - Kelvin Scale
- What is the temperature of absolute zero on the Celsius scale? - $-273.15^\circ\text{C}$
- What is the SI unit of density? - $\text{kg/m}^3$
- What is the latent heat required to change a unit mass from solid to liquid called? - Latent Heat of Fusion
- What is the latent heat required to change a unit mass from liquid to vapor called? - Latent Heat of Vaporization
- Why does ice float on the surface of liquid water? - Density of ice is lower than liquid water
- What state of matter is formed inside fluorescent lamps and neon signs when electrified? - Plasma
2. Acids, Bases, and Salts
- Who first devised and introduced the pH scale in 1909? - S.P.L. Sørensen
- What does the letter 'p' stand for in the abbreviation pH? - Potenz (Power in German)
- What is the pH value of a completely neutral aqueous solution at 25°C? - 7.0
- Aqueous solutions having a pH value less than 7 are classified as what? - Acidic
- Aqueous solutions having a pH value greater than 7 are classified as what? - Basic (Alkaline)
- What is the normal physiological pH range of healthy human blood? - 7.35 to 7.45 (Slightly Alkaline)
- What is the typical pH value of human saliva in a rested, normal state? - 6.5 to 7.5
- What is the typical pH value of pure fresh lemon juice? - 2.2 to 2.4
- What is the pH value of human gastric juice inside the stomach? - 1.5 to 3.5
- Precipitation is officially classified as 'Acid Rain' when its pH value falls below what? - 5.6
- What is the typical pH range of pure distilled water at 25°C? - 7.0
- What is the typical pH of fresh cow's milk? - 6.5 to 6.7
- What is the typical pH of black coffee? - 5.0
- What is the typical pH of ordinary household vinegar? - 2.4 to 3.4
- What natural pH indicator dye is extracted from lichens? - Litmus
- What color change occurs when blue litmus paper is dipped in an acidic solution? - Turns Red
- What color change occurs when red litmus paper is dipped in a basic solution? - Turns Blue
- What color does the synthetic indicator phenolphthalein turn in an acidic solution? - Colorless
- What color does phenolphthalein turn when added to an alkaline/basic solution? - Pink
- What color does methyl orange indicator exhibit in an acidic medium? - Red / Pink
- What color does methyl orange indicator exhibit in a basic medium? - Yellow
- What color change does a natural turmeric stain show when scrubbed with basic soap? - Reddish-Brown
- What organic acid is naturally present in sour milk and curd (yogurt)? - Lactic Acid
- What organic acid is present in commercial vinegar? - Acetic Acid ($\text{CH}_3\text{COOH}$)
- What organic acid is found in citrus fruits like oranges and lemons? - Citric Acid
- What organic acid is naturally present in tamarind and unripened grapes? - Tartaric Acid
- What acid causes the burning sting of honeybees and red ant bites? - Formic Acid / Methanoic Acid ($\text{HCOOH}$)
- What organic acid is present in tomatoes and spinach? - Oxalic Acid
- What organic acid is abundantly present in apples? - Malic Acid
- What mineral acid is naturally secreted by parietal cells in the human stomach? - Hydrochloric Acid ($\text{HCl}$)
- What commercial acid is known as the 'King of Chemicals' and used in lead batteries? - Sulfuric Acid ($\text{H}_2\text{SO}_4$)
- What are mild basic substances used to neutralize excess stomach acidity called? - Antacids
- Which magnesium compound suspension is widely consumed as a liquid antacid? - Milk of Magnesia ($\text{Mg(OH)}_2$)
- Which common sodium salt is used as a fast-acting household oral antacid? - Sodium Bicarbonate ($\text{NaHCO}_3$)
- Which aluminum compound is commonly formulated into commercial antacid tablets? - Aluminum Hydroxide ($\text{Al(OH)}_3$)
- What chemical reaction occurs when an acid reacts with a base to form salt and water? - Neutralization Reaction
- What gas is briskly evolved when acids react with active metals like zinc? - Hydrogen Gas ($\text{H}_2$)
- What gas is evolved with effervescence when an acid reacts with metal carbonates? - Carbon Dioxide ($\text{CO}_2$)
- What gas turns clear lime water milky due to calcium carbonate formation? - Carbon Dioxide ($\text{CO}_2$)
- What is the chemical formula of common table salt? - Sodium Chloride ($\text{NaCl}$)
- What type of acid completely ionizes in aqueous solution (e.g., $\text{HCl}, \text{H}_2\text{SO}_4$)? - Strong Acid
- What type of acid only partially dissociates in aqueous solution (e.g., $\text{CH}_3\text{COOH}$)? - Weak Acid
- What is the base called that dissolves completely in water (e.g., $\text{NaOH}, \text{KOH}$)? - Alkali
- What acid is used for etch-cleaning and rust removal from metal sheets (Pickling)? - Hydrochloric Acid ($\text{HCl}$)
- What is the 3:1 volumetric mixture of concentrated $\text{HCl}$ and concentrated $\text{HNO}_3$ called? - Aqua Regia
- Which precious noble metals can dissolve completely in Aqua Regia? - Gold (Au) and Platinum (Pt)
- What is a solution that resists changes in pH upon addition of small amounts of acid/base called? - Buffer Solution
- What is the primary buffering system present in human blood plasma? - Carbonic Acid-Bicarbonate Buffer
- What is the chemical formula of caustic soda? - Sodium Hydroxide ($\text{NaOH}$)
- What is the chemical formula of caustic potash? - Potassium Hydroxide ($\text{KOH}$)
3. Metals and Non-Metals (Properties, Rusting and Alloys)
- Which metal is placed at the highest position in the standard chemical reactivity series? - Potassium (K)
- Which metal is the least reactive and found in a native free state at the bottom of the series? - Gold (Au) / Platinum (Pt)
- Which metal exists in a liquid state at normal room temperature (25°C)? - Mercury (Hg)
- Which non-metal element exists in a liquid state at normal room temperature? - Bromine (Br)
- Which two alkali metals are soft enough to be sliced easily with a kitchen knife? - Sodium (Na) and Potassium (K)
- Why are alkali metals like sodium and potassium stored submerged in kerosene oil? - To prevent violent reaction with air and atmospheric moisture
- What physical property of metals allows them to be hammered into thin foils/sheets? - Malleability
- Which element is the most malleable and ductile of all known metals? - Gold (Au)
- What physical property of metals allows them to be drawn into thin electrical wires? - Ductility
- Which metal is the best conductor of electricity and heat? - Silver (Ag)
- Which metal is the second best conductor of electricity and widely used in wiring? - Copper (Cu)
- Which non-metal allotrope is an exceptional conductor of electricity? - Graphite
- Which non-metal allotrope is the hardest naturally occurring substance known? - Diamond
- Which non-metal element exhibits a lustrous, shining surface? - Iodine (I)
- What is the ringing sound produced when metals strike a hard surface called? - Sonorousness
- What chemical formula represents the reddish-brown substance known as rust? - Hydrated Ferric Oxide ($\text{Fe}_2\text{O}_3 \cdot x\text{H}_2\text{O}$)
- What two external environmental factors are mandatory for the rusting of iron? - Oxygen (Air) and Moisture (Water)
- What happens to the overall mass/weight of an iron article when it undergoes rusting? - It Increases
- What industrial process coats iron or steel with a thin zinc layer to prevent rust? - Galvanization
- Which sacrificial metal corrodes first to protect underlying iron in galvanization? - Zinc (Zn)
- What is a homogeneous mixture of two or more metals, or a metal and non-metal, called? - Alloy
- What are the primary constituent metals in the alloy Brass? - Copper (60–70%) and Zinc (30–40%)
- What are the primary constituent metals in the alloy Bronze? - Copper (88–90%) and Tin (10–12%)
- What are the primary constituent elements of Stainless Steel? - Iron, Chromium, Nickel, and Carbon
- Which metal element imparts corrosion resistance to stainless steel by forming a passive layer? - Chromium (Cr)
- What are the constituent metals in the soldering alloy (Solder)? - Lead (Pb) and Tin (Sn)
- What are the constituent metals in the lightweight aerospace alloy Duralumin? - Aluminum, Copper, Magnesium, and Manganese
- What is an alloy called when one of its constituent metals is liquid mercury? - Amalgam
- Which transition metal does not form an amalgam, making it ideal for storing mercury? - Iron (Fe)
- What are the constituent metals in German Silver (which contains zero silver)? - Copper, Zinc, and Nickel
- What are the constituent metals in Gun Metal? - Copper, Tin, and Zinc
- What are the constituent metals in Bell Metal? - Copper and Tin
- What are the constituent metals in the ferromagnetic alloy Alnico? - Aluminum, Nickel, and Cobalt
- What unit expresses the purity of gold, where 24 carats denotes 100% pure gold? - Karat (Carat)
- What is the percentage of pure gold present in standard 22-carat gold jewelry? - 91.6% (22 parts Gold, 2 parts Copper/Silver)
- Which metal forms an amphoteric oxide that reacts with both acids and strong bases? - Aluminum / Zinc
- What oxide film protects aluminum from progressive corrosion when exposed to air? - Aluminum Oxide ($\text{Al}_2\text{O}_3$)
- What electrical process thickens the natural protective oxide coating on aluminum? - Anodizing
- Which transition metal is known as the 'Strategic Metal' due to aerospace applications? - Titanium (Ti)
- Which metal is the most abundant in the Earth's continental crust? - Aluminum (Al)
- Which element is the most abundant non-metal in the Earth's crust? - Oxygen (O)
- What is the primary aluminum mineral ore extracted commercially? - Bauxite ($\text{Al}_2\text{O}_3 \cdot 2\text{H}_2\text{O}$)
- What is the primary iron ore used in industrial blast furnaces? - Hematite ($\text{Fe}_2\text{O}_3$)
- What is the purest commercial form of manufactured iron with minimal carbon? - Wrought Iron
- What is the crude, brittle form of iron extracted directly from a blast furnace? - Pig Iron / Cast Iron
- Which non-metal is stored immersed under water because it spontaneously ignites in air? - White Phosphorus
- What non-metal is used in the vulcanization process to harden natural rubber? - Sulfur (S)
- What non-metal compound forms the active ignition tip of household matchsticks? - Red Phosphorus / Potassium Chlorate
- Which metal has the highest melting point ($3422^\circ\text{C}$) and is used in bulb filaments? - Tungsten (W)
- Which metal has such a low melting point ($29.8^\circ\text{C}$) that it melts on the human palm? - Gallium (Ga) / Cesium (Cs)
4. Carbon and its Compounds
- What unique property of carbon enables it to form long, stable covalent chains? - Catenation
- How many valence electrons does a carbon atom possess in its outermost shell? - 4 (Tetravalent)
- What type of chemical bond does carbon form with other atoms by sharing electrons? - Covalent Bond
- What is the phenomenon of an element existing in multiple physical forms with identical chemical properties? - Allotropy
- What is the geometric hybridization of carbon atoms inside a diamond crystal lattice? - $sp^3$ (Rigid Tetrahedral structure)
- What is the geometric hybridization of carbon atoms inside planar graphite layers? - $sp^2$ (Hexagonal sheets)
- Why does graphite conduct electricity while diamond behaves as an insulator? - Presence of free delocalized electrons in graphite
- Why is graphite slippery and used as a solid industrial machine lubricant? - Weak Van der Waals forces allow layers to slide over each other
- What two-dimensional, single-atom-thick honeycomb allotrope of carbon has high mechanical strength? - Graphene
- What spherical cage-like fullerene molecule consists of 60 carbon atoms? - Buckminsterfullerene ($\text{C}_{60}$)
- What are cylindrical tubular allotropes of carbon with nanometer-scale diameters called? - Carbon Nanotubes (CNTs)
- What are organic chemical compounds composed exclusively of carbon and hydrogen called? - Hydrocarbons
- What are saturated hydrocarbons containing only single carbon-carbon bonds called? - Alkanes (Paraffins)
- What is the general molecular formula for homologous alkanes? - $\text{C}_n\text{H}_{2n+2}$
- What is the simplest alkane compound ($n=1$)? - Methane ($\text{CH}_4$)
- What are unsaturated hydrocarbons containing one or more double bonds called? - Alkenes (Olefins)
- What is the general molecular formula for homologous alkenes? - $\text{C}_n\text{H}_{2n}$
- What is the simplest alkene compound ($n=2$)? - Ethene / Ethylene ($\text{C}_2\text{H}_4$)
- What are unsaturated hydrocarbons containing one or more triple bonds called? - Alkynes
- What is the general molecular formula for homologous alkynes? - $\text{C}_n\text{H}_{2n-2}$
- What is the simplest alkyne compound ($n=2$) used in oxy-acetylene welding? - Ethyne / Acetylene ($\text{C}_2\text{H}_2$)
- What is the primary aromatic hydrocarbon with the ring formula $\text{C}_6\text{H}_6$? - Benzene
- What functional group characterizes alcohols? - Hydroxyl Group ($-\text{OH}$)
- What functional group characterizes carboxylic acids? - Carboxyl Group ($-\text{COOH}$)
- What functional group characterizes aldehydes? - Formyl Group ($-\text{CHO}$)
- What functional group characterizes ketones? - Carbonyl Group ($>\text{C}=\text{O}$)
- What chemical compound is standard commercial drinking alcohol? - Ethanol / Ethyl Alcohol ($\text{C}_2\text{H}_5\text{OH}$)
- What toxic alcohol induces blindness and death upon ingestion? - Methanol / Methyl Alcohol ($\text{CH}_3\text{OH}$)
- What chemical compound is commercial pure acetic acid that freezes into ice-like crystals in winter? - Glacial Acetic Acid
- What sweet, fruity-smelling organic compounds are formed by reacting carboxylic acids with alcohols? - Esters
- What are soaps chemically composed of? - Sodium or Potassium salts of long-chain fatty acids
- What industrial alkaline hydrolysis process converts vegetable oils/fats into soap? - Saponification
- What valuable chemical byproduct is isolated during industrial soap manufacturing? - Glycerol / Glycerin
- What part of a soap molecule is hydrophilic (water-loving) and ionic? - The Ionic Polar Head
- What part of a soap molecule is hydrophobic (water-repelling) and non-polar? - The Long Hydrocarbon Tail
- What spherical molecular aggregate formed by soap molecules traps oily grease in water? - Micelle
- Why do conventional soaps fail to lather effectively in hard water? - They react with $\text{Ca}^{2+}$ and $\text{Mg}^{2+}$ to form insoluble scum
- What synthetic cleansing agents maintain foaming and cleaning power even in hard water? - Detergents (Sodium alkyl sulfates/sulfonates)
- What chemical process converts unsaturated vegetable oils into solid saturated vanaspati ghee? - Hydrogenation
- Which catalyst metal is used in the industrial hydrogenation of vegetable oils? - Finely divided Nickel (Ni)
- What is the main gas released during the complete combustion of hydrocarbons in excess air? - Carbon Dioxide ($\text{CO}_2$)
- What poisonous gas is formed during the incomplete combustion of fuels in limited oxygen? - Carbon Monoxide ($\text{CO}$)
- Why is carbon monoxide fatal to breathe in closed rooms? - It binds with blood hemoglobin to form Carboxyhemoglobin
- What natural polymer made of glucose units forms plant cell walls? - Cellulose
- What synthetic polyamide polymer was first marketed as synthetic silk stockings? - Nylon-6,6
- What was the first commercially synthesized thermosetting plastic? - Bakelite
- Which monomer unit polymerizes to synthesize Polythene? - Ethene (Ethylene)
- Which polymer is known by the commercial trade name Teflon? - Polytetrafluoroethylene (PTFE)
- Why is Teflon used to coat non-stick cooking cookware? - High heat resistance and non-adhesive properties
- What polymer is commercially fabricated into drainage pipes (PVC)? - Polyvinyl Chloride
5. Everyday Chemicals and Common Names
- What is the common household name of Sodium Bicarbonate ($\text{NaHCO}_3$)? - Baking Soda
- What is the chemical formula of Baking Soda? - $\text{NaHCO}_3$
- What mixture of Baking Soda and a mild edible acid (like Tartaric Acid) is used in baking? - Baking Powder
- What gas released from baking powder causes cake dough to rise and become spongy? - Carbon Dioxide ($\text{CO}_2$)
- What is the common name of Sodium Carbonate Decahydrate ($\text{Na}_2\text{CO}_3 \cdot 10\text{H}_2\text{O}$)? - Washing Soda
- What is the chemical formula of Washing Soda? - $\text{Na}_2\text{CO}_3 \cdot 10\text{H}_2\text{O}$
- How many molecules of water of crystallization are present in one formula unit of washing soda? - 10 Molecules
- What chemical compound is used industrially to remove permanent hardness of water? - Washing Soda ($\text{Na}_2\text{CO}_3$)
- What is the chemical name of Bleaching Powder? - Calcium Oxychloride / Hypochlorite ($\text{CaOCl}_2$)
- What is the chemical formula of Bleaching Powder? - $\text{CaOCl}_2$
- What gas is passed over dry slaked lime ($\text{Ca(OH)}_2$) to manufacture bleaching powder? - Chlorine Gas ($\text{Cl}_2$)
- What chemical is used as a disinfectant in municipal tap water treatment plants? - Bleaching Powder / Chlorine
- What is the common name of Calcium Sulfate Hemihydrate ($\text{CaSO}_4 \cdot \frac{1}{2}\text{H}_2\text{O}$)? - Plaster of Paris (POP)
- What is the chemical formula of Plaster of Paris? - $\text{CaSO}_4 \cdot \frac{1}{2}\text{H}_2\text{O}$
- What mineral substance is heated to $373\text{ K}$ ($100^\circ\text{C}$) to produce Plaster of Paris? - Gypsum ($\text{CaSO}_4 \cdot 2\text{H}_2\text{O}$)
- What is the chemical formula of Gypsum? - $\text{CaSO}_4 \cdot 2\text{H}_2\text{O}$
- What chemical substance is used by orthopedic doctors to set fractured bones in position? - Plaster of Paris
- What is the common name of Calcium Oxide ($\text{CaO}$)? - Quicklime
- What is the chemical formula of Quicklime? - $\text{CaO}$
- What is the common name of Calcium Hydroxide ($\text{Ca(OH)}_2$)? - Slaked Lime
- What is the chemical formula of Slaked Lime? - $\text{Ca(OH)}_2$
- What is the clear aqueous solution of slaked lime commonly called? - Lime Water
- What is the common name of Nitrous Oxide ($\text{N}_2\text{O}$)? - Laughing Gas
- What is the chemical formula of Laughing Gas? - $\text{N}_2\text{O}$
- What gas is used as a dental anesthetic and mood-elevating inhalant? - Nitrous Oxide ($\text{N}_2\text{O}$)
- What common chemical compound is deployed for crowd control as Tear Gas? - Chloroacetophenone / CS Gas
- What is the commercial name of Sodium Hydroxide ($\text{NaOH}$)? - Caustic Soda
- What is the commercial name of Potassium Hydroxide ($\text{KOH}$)? - Caustic Potash
- What is the chemical name of Blue Vitriol? - Copper Sulfate Pentahydrate ($\text{CuSO}_4 \cdot 5\text{H}_2\text{O}$)
- What is the chemical formula of Blue Vitriol? - $\text{CuSO}_4 \cdot 5\text{H}_2\text{O}$
- What is the chemical name of Green Vitriol? - Ferrous Sulfate Heptahydrate ($\text{FeSO}_4 \cdot 7\text{H}_2\text{O}$)
- What is the chemical formula of Green Vitriol? - $\text{FeSO}_4 \cdot 7\text{H}_2\text{O}$
- What is the chemical name of White Vitriol? - Zinc Sulfate Heptahydrate ($\text{ZnSO}_4 \cdot 7\text{H}_2\text{O}$)
- What is the chemical formula of White Vitriol? - $\text{ZnSO}_4 \cdot 7\text{H}_2\text{O}$
- What is the chemical name of Oil of Vitriol? - Concentrated Sulfuric Acid ($\text{H}_2\text{SO}_4$)
- What chemical compound is commonly known as Epsom Salt? - Magnesium Sulfate Heptahydrate ($\text{MgSO}_4 \cdot 7\text{H}_2\text{O}$)
- What is the chemical name and formula of common Alum (Fitkari)? - Potassium Aluminum Sulfate ($\text{KAl(SO}_4)_2 \cdot 12\text{H}_2\text{O}$)
- Why is alum added to turbid muddy water during water purification? - To coagulate suspended colloidal clay particles
- What chemical compound is known as Chile Saltpeter? - Sodium Nitrate ($\text{NaNO}_3$)
- What chemical compound is known as Indian Saltpeter? - Potassium Nitrate ($\text{KNO}_3$)
- What is the chemical formula of marble, chalk, and limestone? - Calcium Carbonate ($\text{CaCO}_3$)
- What chemical compound is used as voting ink marked on fingernails in elections? - Silver Nitrate ($\text{AgNO}_3$)
- What chemical compound is used in artificial cloud seeding to induce rain? - Silver Iodide ($\text{AgI}$)
- What chemical compound was historically used in black-and-white photography film? - Silver Bromide ($\text{AgBr}$)
- What is the chemical name of household mothballs? - Naphthalene / Paradichlorobenzene
- What is the chemical name of heavy water used as a reactor moderator? - Deuterium Oxide ($\text{D}_2\text{O}$)
- What chemical compound is known as White Lead? - Basic Lead Carbonate
- What is the chemical name of Vermilion (Sindoor)? - Mercuric Sulfide ($\text{HgS}$ / Cinnabar)
- What chemical substance is known as Lunar Caustic? - Silver Nitrate ($\text{AgNO}_3$)
- What is the chemical formula of Carborundum, an industrial abrasive? - Silicon Carbide ($\text{SiC}$)
6. Gases, Fuels, and Combustion
- What are the two primary hydrocarbon gas components of Liquefied Petroleum Gas (LPG)? - Butane and Propane
- Which hydrocarbon represents the single largest component in domestic LPG cylinders? - Butane ($\text{C}_4\text{H}_{10}$)
- What sulfur odorant compound is added to LPG cylinders to detect accidental gas leaks? - Ethyl Mercaptan ($\text{C}_2\text{H}_5\text{SH}$)
- What is the primary gaseous hydrocarbon component of Compressed Natural Gas (CNG)? - Methane ($\text{CH}_4$) (approx. 85–90%)
- What is the primary combustible gas component in Biogas (Gobar Gas)? - Methane ($\text{CH}_4$) (55–70%)
- What is the synthetic fuel gas mixture of Carbon Monoxide and Hydrogen ($\text{CO} + \text{H}_2$) called? - Water Gas (Synthesis Gas)
- What is the fuel gas mixture of Carbon Monoxide and Nitrogen ($\text{CO} + \text{N}_2$) called? - Producer Gas
- What is the synthetic gas mixture of methane, hydrogen, and carbon monoxide from coal called? - Coal Gas
- Which highest grade of coal contains the maximum carbon percentage (over 90%) and calorific value? - Anthracite
- Which grade of coal is the most abundant and widely burned in thermal power stations? - Bituminous Coal
- Which low-grade coal is known as 'Brown Coal' and has high moisture content? - Lignite
- What is the uncompacted first stage in the geological formation of coal? - Peat
- Which element's combustion produces the highest calorific value of all known fuels? - Hydrogen Gas ($\text{H}_2$) (approx. $150\text{ kJ/g}$)
- Why is hydrogen gas designated as the 'Fuel of the Future'? - High calorific efficiency and zero greenhouse emissions (yields water)
- What metric measures the antiknock quality of gasoline/petrol fuel in internal combustion engines? - Octane Number
- What metric measures the ignition delay and quality of diesel fuel? - Cetane Number
- What organolead compound was historically blended into petrol as an antiknock additive? - Tetraethyl Lead (TEL)
- What is the primary greenhouse gas emitted by the burning of fossil fuels? - Carbon Dioxide ($\text{CO}_2$)
- What greenhouse gas is released from flooded agricultural paddy fields and cattle enteric fermentation? - Methane ($\text{CH}_4$)
- What potent greenhouse gas is emitted from industrial nitrogenous fertilizer use? - Nitrous Oxide ($\text{N}_2\text{O}$)
- Which synthetic refrigerant gases are responsible for stratospheric ozone layer depletion? - Chlorofluorocarbons (CFCs / Freons)
- What international treaty signed in 1987 phased out the production of CFCs? - Montreal Protocol
- What international treaty adopted in 1997 mandated reduction targets for greenhouse gases? - Kyoto Protocol
- What toxic gas is emitted from incomplete vehicle exhaust and smoldering charcoal stoves? - Carbon Monoxide ($\text{CO}$)
- What two atmospheric pollutant gases dissolve in rainwater to precipitate Acid Rain? - Sulfur Dioxide ($\text{SO}_2$) and Nitrogen Oxides ($\text{NO}_x$)
- What toxic gas leaked during the Bhopal Gas Disaster on December 2–3, 1984? - Methyl Isocyanate (MIC)
- What chemical compound was used in the gas chambers during World War II? - Hydrogen Cyanide (Zyklon B)
- What inert noble gas is filled inside illuminated electric light bulbs? - Argon (Ar) / Nitrogen ($\text{N}_2$)
- What noble gas is used in bright, glowing orange-red advertising display boards? - Neon (Ne)
- What non-flammable noble gas is filled inside high-altitude meteorological weather balloons? - Helium (He)
- What noble gas is used as an anesthetic in specialized medical imaging? - Xenon (Xe)
- What radioactive noble gas accumulates in basements from natural bedrock decay? - Radon (Rn)
- What gas is dissolved under pressure in carbonated soda drinks to provide fizz? - Carbon Dioxide ($\text{CO}_2$)
- What gas is used in municipal cylinders for the artificial ripening of green raw fruits? - Acetylene ($\text{C}_2\text{H}_2$) / Ethylene
- What gas is filled inside automobile safety airbags that inflates instantly upon impact? - Nitrogen Gas ($\text{N}_2$) (from Sodium Azide decomposition)
- What gas produces a pungent suffocating odor during volcanic eruptions and near thermal springs? - Sulfur Dioxide ($\text{SO}_2$)
- What gas smells like rotten eggs and turns lead acetate paper black? - Hydrogen Sulfide ($\text{H}_2\text{S}$)
- What gas is manufactured via the industrial Haber-Bosch catalytic process? - Ammonia ($\text{NH}_3$)
- What solid catalyst is used in the industrial Haber process for ammonia synthesis? - Finely divided Iron (Fe) with Molybdenum (Mo) promoter
- What industrial catalytic process is used for the large-scale manufacture of Sulfuric Acid? - Contact Process
- What catalyst is used in the Contact Process for sulfuric acid? - Vanadium Pentoxide ($\text{V}_2\text{O}_5$)
- What industrial process manufactures Nitric Acid ($\text{HNO}_3$) via the oxidation of ammonia? - Ostwald’s Process
- What gas is released when bleaching powder is left exposed to atmospheric air? - Chlorine Gas ($\text{Cl}_2$)
- What is the lowest temperature at which a fuel catches fire and burns spontaneously? - Ignition Temperature
- What chemical compound in fire extinguishers reacts to produce smothering $\text{CO}_2$ gas? - Sodium Bicarbonate + Sulfuric Acid
- Which region of a candle flame is the hottest and non-luminous? - Outer Blue Zone (Zone of Complete Combustion)
- Which region of a candle flame is luminous, yellow, and moderately hot? - Middle Zone (Zone of Incomplete Combustion)
- What is the dark, cool innermost region surrounding the wick of a burning candle? - Innermost Zone (Unburnt wax vapors)
- What type of combustion occurs instantly without an external ignition source (e.g., White Phosphorus)? - Spontaneous Combustion
- What type of rapid chemical combustion produces light, heat, and large gas volumes explosively? - Explosion
7. Atomic Structure and Periodic Table
- Who discovered the negatively charged subatomic particle known as the Electron in 1897? - J.J. Thomson (via Cathode Ray Tube)
- What is the magnitude of electric charge carried by a single electron? - $-1.602 \times 10^{-19}\text{ Coulombs}$
- What is the rest mass of an electron? - $9.109 \times 10^{-31}\text{ kg}$
- Who discovered the positively charged atomic nucleus via the Gold Foil Experiment in 1911? - Ernest Rutherford
- Who is credited with the discovery and naming of the Proton? - Ernest Rutherford (and Eugen Goldstein)
- What is the rest mass of a proton? - $1.672 \times 10^{-27}\text{ kg}$
- Who discovered the uncharged neutral subatomic particle known as the Neutron in 1932? - James Chadwick
- What is the mass of a neutron relative to a proton? - Slightly heavier than a proton ($1.675 \times 10^{-27}\text{ kg}$)
- Which common element's lightest atom has zero neutrons in its nucleus? - Protium ($^1\text{H}$ / Normal Hydrogen)
- What subatomic particles reside inside the central atomic nucleus? - Protons and Neutrons (together called Nucleons)
- What fundamental force binds protons and neutrons together inside the atomic nucleus? - Strong Nuclear Force
- What is defined as the total number of protons present inside an atom's nucleus? - Atomic Number ($Z$)
- What is defined as the sum total of protons and neutrons in an atom's nucleus? - Mass Number ($A$)
- What are atoms of the same element having the same atomic number but different mass numbers called? - Isotopes
- What are the three natural isotopes of hydrogen? - Protium ($^1\text{H}$), Deuterium ($^2\text{H}$), and Tritium ($^3\text{H}$)
- Which natural isotope of hydrogen is radioactive and emits beta particles? - Tritium ($^3\text{H}$)
- Which radioisotope is used in carbon dating to determine the age of archaeological fossils? - Carbon-14 ($^{14}\text{C}$)
- Which radioisotope is used in medical radiation therapy to treat cancerous tumors? - Cobalt-60 ($^{60}\text{Co}$)
- Which radioisotope is used in the clinical diagnosis and treatment of thyroid gland disorders? - Iodine-131 ($^{131}\text{I}$)
- Which radioisotope of uranium serves as fuel in nuclear fission reactors? - Uranium-235 ($^{235}\text{U}$)
- What are atoms of different chemical elements having the same mass number but different atomic numbers called? - Isobars
- What is an example of an isobaric pair? - Argon-40 ($^{40}_{18}\text{Ar}$) and Calcium-40 ($^{40}_{20}\text{Ca}$)
- What are atoms of different chemical elements that have the exact same number of neutrons called? - Isotones
- What are atoms or molecules possessing the exact same number of electrons called? - Isoelectronic Species
- Who proposed the planetary atomic model with quantized circular electron energy orbits in 1913? - Niels Bohr
- What is the formula for the maximum electron capacity of an atomic shell with principal quantum number $n$? - $2n^2$
- How many electrons can be accommodated in the $K$-shell ($n=1$)? - 2 Electrons
- How many electrons can be accommodated in the $L$-shell ($n=2$)? - 8 Electrons
- How many electrons can be accommodated in the $M$-shell ($n=3$)? - 18 Electrons
- How many electrons can be accommodated in the $N$-shell ($n=4$)? - 32 Electrons
- Which principle states that electrons fill lower-energy atomic orbitals before occupying higher ones? - Aufbau Principle
- Which rule states that no two electrons in an atom can have the exact same set of four quantum numbers? - Pauli’s Exclusion Principle
- Which rule governs electron pairing in degenerate orbitals (pairing starts only after single occupancy)? - Hund’s Rule of Maximum Multiplicity
- Who proposed the wave-particle duality of matter ($\lambda = \frac{h}{mv}$)? - Louis de Broglie
- Who formulated the Uncertainty Principle ($\Delta x \cdot \Delta p \ge \frac{h}{4\pi}$)? - Werner Heisenberg
- Who created the first periodic table arranged by increasing atomic masses in 1869? - Dmitri Mendeleev
- What periodic anomaly in Mendeleev's table was resolved by using atomic numbers? - Placement of Isotopes and inverted pairs (e.g., $\text{Co}$ and $\text{Ni}$)
- Who formulated the Modern Periodic Law arranging elements by increasing atomic number ($Z$)? - Henry Moseley
- How many horizontal Periods and vertical Groups comprise the modern Long Form Periodic Table? - 7 Periods and 18 Groups
- What are the elements belonging to Group 1 of the periodic table called? - Alkali Metals
- What are the elements belonging to Group 2 of the periodic table called? - Alkaline Earth Metals
- What are the elements belonging to Groups 3 through 12 called? - Transition Metals (d-block)
- What are the elements belonging to Group 17 called? - Halogens
- What are the inert, unreactive elements of Group 18 called? - Noble Gases (Inert Gases)
- Which chemical element in the periodic table possesses the highest electronegativity? - Fluorine (F)
- Which chemical element in the periodic table possesses the highest electron affinity? - Chlorine (Cl)
- Which chemical element possesses the lowest ionization energy? - Cesium (Cs)
- What happens to atomic radius when moving from left to right across a period in the periodic table? - It Decreases (due to increasing effective nuclear charge)
- What happens to atomic radius when descending down a group in the periodic table? - It Increases (due to addition of new electron shells)
- What elements comprise the two 14-element series placed separately at the bottom of the periodic table? - Lanthanides (4f) and Actinides (5f)