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Allgemeine Chemie I — Atoms, Bonds & Reactions
by MonaA deep, Socratic preparation for the first semester of university chemistry, modeled on the Allgemeine Chemie lecture at the University of Hamburg. Starting from the evidence that atoms are real, the course builds up the quantum picture of the atom, uses it to explain the logic of the periodic table, then constructs bonding, molecular shapes, and intermolecular forces — finishing with the quantitative skills (stoichiometry, balancing reactions) every first-year exam demands. Each lesson develops one core idea through questions, predictions, and problems rather than memorization.
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Lesson 1
The Balance That Proved the Invisible
In 1803 no microscope on Earth could see an atom — yet chemists became certain atoms existed, armed with nothing but a beam balance. What could weighing things possibly prove about the invisible?
StartLesson 2
The Atom's Barcode
Heat or electrify any element and it glows in only a few razor-sharp colors — hydrogen always the same four lines, sodium always the same yellow. Why would nature forbid every color in between?
StartLesson 3
Where Is the Electron, Really?
Bohr drew electrons on neat circular orbits — and he was wrong. What replaced the orbit is far stranger.
Locked till you take the prior lessonLesson 4
The Quantum Address System
Every electron in every atom has a unique four-part address. Crack the code and orbital shapes start making sense.
Locked till you take the prior lessonLesson 5
Building Atoms Electron by Electron
Given 26 electrons and a set of empty orbitals, could you assemble an iron atom? Nature follows exactly three rules.
Locked till you take the prior lessonLesson 6
Why the Periodic Table Has Its Shape
Why is the periodic table that odd castle shape — two towers, a wide middle, a floating basement? It's not a design choice.
Locked till you take the prior lessonLesson 7
Periodic Trends
A cesium atom is enormous; a helium atom is tiny. Fluorine is a ferocious electron thief. One tug-of-war explains it all.
Locked till you take the prior lessonLesson 8
Ionic Bonding
Sodium explodes in water; chlorine gas is poison. Combined, they're table salt. What actually happens between those two atoms?
Locked till you take the prior lessonLesson 9
Covalent Bonding & Lewis Structures
Two chlorine atoms both want an extra electron and neither will give one up. So how do they ever bond?
Locked till you take the prior lessonLesson 10
Molecular Shapes (VSEPR)
CO₂ is a straight line but H₂O is bent — and that tiny kink is why life exists. Can you predict a molecule's shape?
Locked till you take the prior lessonLesson 11
Polarity & Intermolecular Forces
Water should be a gas at room temperature — similar-sized molecules all are. Something invisible holds it together. What?
Locked till you take the prior lessonLesson 12
Stoichiometry Mastery
A rocket engineer who mixes fuel and oxygen in the wrong ratio wastes tons of payload. Chemistry's accounting skills start here.
Locked till you take the prior lessonLesson 13
Reaction Types & Equations
Thousands of reactions, but almost all fall into just a few families. Learn to recognize them on sight — and balance anything.
Locked till you take the prior lesson