Class 12 Chemistry
Pick a chapter to see its topics and videos, in the order your textbook follows.
1Solutions1 video28 topics planned2ElectrochemistryVideos coming soon28 topics planned3Chemical KineticsVideos coming soon22 topics planned4The d- and f-Block Elements7 videos23 topics planned5Coordination CompoundsVideos coming soon21 topics planned6Haloalkanes and HaloarenesVideos coming soon19 topics planned7Alcohols, Phenols and EthersVideos coming soon18 topics planned8Aldehydes, Ketones and Carboxylic Acids24 videos9AminesVideos coming soon15 topics planned10BiomoleculesVideos coming soon18 topics planned
Aldehyde or Ketone? Structure and IUPAC NamesMethanal and propanone both have C=O, yet one is an aldehyde and one a ketone. Where the C=O sits decides it, and the names follow: -al for aldehydes, -one for ketones, plus the common names.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Aldehyde or Ketone? The Distinguishing TestsTwo colourless compounds, both with C=O. How Tollens', Fehling's and the iodoform test tell an aldehyde from a ketone, and why they work.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
Aldehyde vs Ketone: Why Aldehydes React FasterBoth have the same C=O, yet a nucleophile attacks an aldehyde faster. Two reasons: alkyl groups push electrons (+I) and lower the carbonyl carbon's δ+, and a ketone's two groups crowd the path to it. So HCHO > CH₃CHO > CH₃COCH₃.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Aldehydes, Ketones and Carboxylic Acids: Chapter IntroductionVanilla, cinnamon, vinegar and nail-polish remover share one secret: the carbonyl group, C=O. What sits on the carbonyl carbon makes an aldehyde, a ketone or a carboxylic acid, and what this chapter will cover.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Aldehydes, Ketones and Carboxylic Acids: The Whole Chapter in One MinuteThe chapter in one place: the polar, planar C=O group; how aldehydes and ketones are made; nucleophilic addition; aldol and Cannizzaro; Tollens' and Fehling's tests; and why carboxylic acids are acidic.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Aldol Condensation: The Alpha Hydrogen KeyTwo small ethanal molecules join into one bigger molecule. How the alpha hydrogen makes it happen, and which compounds cannot do it.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
d-Block Configurations: Why Chromium and Copper Break the RuleThe d-block's general configuration is (n−1)d¹⁻¹⁰ ns¹⁻², with 4s filling before 3d. Chromium (3d⁵4s¹) and copper (3d¹⁰4s¹) move one 4s electron into 3d, because 3d and 4s are very close in energy and half-filled and full d sets are extra stable.The d- and f-Block Elements · Chemistry
Esterification and the C–OH Swap: Esters, Acid Chlorides, Anhydrides, AmidesFruity esters from an acid and an alcohol, with the acid-catalysed mechanism drawn arrow by arrow, and three more ways to replace the –OH of –COOH: acid chlorides (best with SOCl₂), anhydrides and amides.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Five More Protons, Same Size: Radius and Ionisation Enthalpy across the 3d SeriesAcross the 3d series each new electron enters the inner (n−1)d subshell and shields the outer 4s electrons, nearly cancelling the extra nuclear charge. So atomic radii change only slightly and the first ionisation enthalpy rises slowly (631 → 906 kJ/mol), unlike across a normal period.The d- and f-Block Elements · Chemistry
HVZ Reaction and Why Benzoic Acid Goes MetaTwo places a carboxylic acid can be substituted: the α-carbon (HVZ: X₂ and red phosphorus, then water) and the benzene ring of an aromatic acid, where –COOH is deactivating and meta-directing and blocks Friedel-Crafts reactions.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Losing CO₂: Decarboxylation, Kolbe Electrolysis and ReductionHow the –COOH group itself changes: soda lime removes it as CO₂ (one carbon less), Kolbe electrolysis joins two alkyl groups, and LiAlH₄ or diborane reduces it to a primary alcohol, while NaBH₄ cannot.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Making Aldehydes and Ketones: Methods and Named ReactionsFour routes make both aldehydes and ketones (from alcohols, alkenes and alkynes); named reactions make only one: Rosenmund, Stephen, Etard and Gatterman-Koch for aldehydes; Grignard on nitriles, dialkylcadmium and Friedel-Crafts acylation for ketones.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Nucleophilic Addition Reactions: One Carbonyl, Five PathwaysEvery nucleophilic addition reaction of aldehydes and ketones in one place: HCN, NaHSO₃, Grignard reagents, alcohols, and the addition–elimination of ammonia derivatives, with the product each one gives.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
Nucleophilic Addition to the Carbonyl GroupMost reactions of aldehydes and ketones begin with one move. How a nucleophile attacks the polar C=O, and why aldehydes react faster than ketones.Aldehydes, Ketones and Carboxylic Acids · Chemistry
One Element, Six Oxidation States: Why Transition Metals VaryThe ns and (n−1)d electrons of a transition metal are close in energy, so both can take part in bonding. Manganese (3d⁵ 4s²) shows every state from +2 to +7; the most states occur in the middle of the series, Sc shows only +3 and Zn only +2, and the states change in steps of one.The d- and f-Block Elements · Chemistry
Preparing Carboxylic Acids: Four RoutesFour ways to make a carboxylic acid: oxidising primary alcohols and aldehydes, oxidising alkylbenzenes, hydrolysing nitriles and esters, and adding a Grignard reagent to dry ice, which adds one carbon (mechanism with curved arrows).Aldehydes, Ketones and Carboxylic Acids · Chemistry
Reducing and Oxidising Aldehydes and KetonesReduction is easy for both aldehydes and ketones, but in oxidation the aldehyde reacts at once and the ketone resists. The reason is one H atom.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
Same Weight, 0 °C vs 97 °C: Physical Properties of Aldehydes and KetonesFive compounds of the same mass boil from 0 °C to 97 °C. Aldehydes and ketones sit in the middle: their polar C=O gives dipole-dipole attraction, but with no O–H they cannot hydrogen-bond with each other. Water can hydrogen-bond to the C=O oxygen, so small aldehydes and ketones mix with water while long chains do not.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Solutions: Chapter IntroductionSoda fizzes when opened and the sea does not freeze at 0 °C: both are solution behaviour. The chapter covers concentration, Henry's and Raoult's laws and colligative properties.Solutions · Chemistry
The Cannizzaro ReactionTwo identical aldehyde molecules, two different products. How an aldehyde with no α-hydrogen, in concentrated alkali, is oxidised and reduced in the same reaction.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
The Carbonyl Group: Structure and PolarityWhy the carbon of C=O is every nucleophile's target: an sp², planar carbon, a π bond from sideways p–p overlap, and a polar C=O with δ⁺ carbon and δ⁻ oxygen, explained by resonance.Aldehydes, Ketones and Carboxylic Acids · Chemistry
The Carboxyl Group: Structure and NamingWhat –COOH really is: a carbonyl and a hydroxyl on one sp² carbon, joined by resonance that makes the carbon less electrophilic than in aldehydes; and how carboxylic acids get their common and IUPAC names.Aldehydes, Ketones and Carboxylic Acids · Chemistry
The d- and f-Block Elements: Chapter IntroductionIron bridges, copper wires and bright blue, purple and orange solutions all come from one part of the periodic table. The d-block (groups 3–12) fills d orbitals; the f-block (two rows below) fills f orbitals. Variable oxidation states, colour, magnetism and catalysis make them special.The d- and f-Block Elements · Chemistry
The Haloform Reaction: Iodoform TestYellow crystals with a hospital smell reveal the CH₃CO group. How the iodoform test works and which compounds pass it.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
Tollens' and Fehling's TestsWarm a clear liquid and a mirror forms in the test tube. How Tollens' and Fehling's tests tell aldehydes from ketones.Aldehydes, Ketones and Carboxylic Acids · Chemistry · simulation
Uses of Aldehydes and Ketones: From Formalin to VanillaWhere aldehydes and ketones turn up in daily life: formalin and Bakelite from formaldehyde, acetic acid from acetaldehyde, acetone as a solvent, and vanillin, cinnamaldehyde and benzaldehyde as smells and flavours, each explained from its C=O group.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Vinegar to Nylon: Uses of Carboxylic AcidsWhere carboxylic acids are used: formic acid in industry, acetic acid as a solvent and vinegar, adipic acid for nylon-6,6 through amide links, sodium benzoate as a food preservative, fatty-acid salts as soap, and aspirin as a medicine.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Why Carboxylic Acids Are Acidic: Resonance and SubstituentsWhy vinegar fizzes with baking soda: the carboxylate ion shares its charge equally between two oxygens (resonance, arrow by arrow), which makes carboxylic acids stronger than phenols and alcohols; electron-withdrawing groups such as chlorine make them stronger still.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Why Carboxylic Acids Boil So High: Hydrogen-Bonded DimersFour molecules of about the same mass boil from 0 °C to 118 °C. Carboxylic acids win because two hydrogen bonds join them into dimers that survive even in the vapour; the same dimers double acetic acid's measured molar mass in benzene.Aldehydes, Ketones and Carboxylic Acids · Chemistry
Why Transition Metals Have High Melting PointsIn transition metals the (n−1)d electrons join the ns electrons in metallic bonding, so the bonds are strong and the metals are hard with high melting points. Across the 3d series melting points peak near the middle (Mn is an exception) and fall to zinc (d¹⁰).The d- and f-Block Elements · Chemistry
Zinc Fizzes, Copper Stays Silent: Electrode Potentials of the 3d MetalsCopper is the only 3d metal with a positive E°(M²⁺/M) (+0.34 V), so it gives no H₂ with dilute acids. Turning Cu(s) into Cu²⁺(aq) costs more (atomisation + two ionisations) than hydration pays back: 921 against zinc's 711 kJ/mol. Stable d⁵ and d¹⁰ bend the trend: Mn and Zn dip, Mn³⁺ is a strong oxidant, Fe³⁺ is stable.The d- and f-Block Elements · Chemistry
Zinc Is in the d-Block, So Why Is It Not a Transition Metal?A transition element has an incompletely filled d subshell in its atom or in a common ion. Iron (3d⁶) passes; copper (3d¹⁰ atom) passes through Cu²⁺ (3d⁹); zinc stays 3d¹⁰ even as Zn²⁺, so Zn, Cd and Hg are d-block but not transition metals.The d- and f-Block Elements · ChemistryNo topic matches. Try a shorter word.