- Hatsudy
- Elementary Math
- Calculating the Volume and Capacity of Cubes and Cuboids
- Enlargement and Reduction, Scale: Geometric Figures in Elementary Math
- Line and Point Symmetry: Congruent Shapes in Elementary Math
- Circumference and Area of a Circle: Calculating with Pi
- Calculating the Area of Quadrilaterals and Triangles: Elementary Math Geometry
- Angles and Types of Triangles and Quadrilaterals: Elementary Math Geometry and Polygons
- Right Angles, Perpendicular Lines, and Parallel Lines: Ggeometry in Elementary Math
- Conversion Between Fractions and Decimals
- Dividing Fractions: Using Reciprocals and Flipping the Numerator and Denominator
- Multiplying Fractions: Multiplication Methods and Simplifying Fractions
- Adding and Subtracting Fractions: Same and Different Denominators
- Addition and Subtraction of Numbers up to 10 in Elementary School Math
- Simplifying Fractions and Finding Least Common Denominators
- Basics of Fractions: Concept of Numerator and Denominator, Proper Fractions, Improper Fractions, and Mixed Fractions
- Even and Odd Numbers: How to Distinguish and Remember in Math
- Factors and Multiples: Greatest Common Divisor and the Least Common Multiple
- Division of Decimals: Quotient and Remainder Calculations and Long Division
- Multiplication of Decimals: Decimal Point Position and How to Solve Problems
- Adding and Subtracting Decimals: How to Calculate in Math
- Rounding Numbers: Elementary Math with Approximate Numbers
- Order of Operations: The Rules of the Four Arithmetic Operations in Elementary Math
- Division and Remainders: Long Division in Elementary Math
- Multiplication of Integers: Long Multiplication in Elementary Arithmetic
- Addition and Subtraction: Arithmetic of Carrying and Borrowing

- Marketing
- Organic Chemistry
- Aromatic Heterocyclic Compounds: Reactivity and Orientation
- Diels-Alder Reaction of Pericyclic Reactions: Dienes and Dienophiles
- Conjugated Dienes and Michael Addition: 1,2 Addition and 1,4 Addition
- Aldol Reaction and Aldol Condensation: Enolate Synthesis by Acid and Base
- Claisen Condensation and Dieckmann Condensation: Decarboxylation, Choice of Base
- Enol and Enolate: α-Carbon of Carbonyl Group and Alkylation
- Catalytic Hydrogenation: Catalytic Reduction of Pd/C, Deprotection and Lindlar Catalyst
- Carbonyl Reduction: Hydride Reduction with NaBH4 and LiAlH4
- Wittig Reaction: Synthesis of Alkenes from Ylides and Carbonyl Compounds
- HSAB Theory: Meaning the Hard/Soft of Acids and Bases
- Nucleophilic Acyl Substitution with Carboxylic Acid Derivatives
- Hydration of Carbonyl Compounds: Acetal Hemiacetal and Protecting Groups
- Ketones and Aldehydes: Nucleophilic Addition Reaction and Imine/Enamines
- Nucleophilic Aromatic Substitution: Sandmeyer Reaction and Benzyne
- Electrophilic Aromatic Substitution: Friedel-Crafts Reaction and Reactivity of Benzene Rings
- Amines and Thiols: Reactivity of Nucleophilic Substitution and Elimination Reactions
- Organometallic Compounds: Grignard Reagent and Organolithium Reagent
- Radical Reactions: Homolysis, Chain Reaction, and Regioselectivity Reaction Mechanisms
- Reactions of Alcohol: Oxidation and Substitution Reactions by Bases and Acids
- Reactivity of Ethers and Epoxides: Synthesis and Cleavage Reactions
- Addition Reactions of Alkynes: Acidity and Acetylide Synthesis
- Addition Reactions of Alkenes: Markovnikov's Rule, Hydroboration and Halogenation
- Optical Isomers: RS Notation of Chirality / Enantiomers and Diastereomers
- Cyclohexane Conformation: Chair Conformation and Axial Equatorial Stability
- Alkane Conformation: Newman projection and Anti-Gauche form Strain
- Lewis Acid and Base: Brønsted Conjugate Acids and Bases
- Elimination Reaction: Create Double Bond with E1 and E2 reactions
- Nucleophilic Substitution: Distinguish SN1 and SN2 Reactions
- IUPAC Nomenclature: the Concept of Hydrocarbon Main Chains and Priority
- Stability of Carbocation and Radicals: Delocalization by Hyperconjugation
- Orientation and Reactivity of Aromatic Compounds: Ortho, Meta, Para
- Inductive and Resonance Effects: Electron Donating and Electron Withdrawing Groups
- Resonance Structures: Movement of Electrons and How to Write Stable Structures
- Writing Lewis Structures and Octet Rule: Electrons Stable States and Exceptions
- HOMO and LUMO: Energy of Bonding Orbital and Antibonding Orbital
- Pauli Exclusion Principle and Hund's Rules: Learn About Electron Placement and Orbits
- s and p orbitals, sp3, sp2, sp Hybrid Orbitals: The Concept of Hybridization and Electronic Orbitals
- σ- and π-bonds: Differences in Energy, Reactivity, meaning of Covalent and Double Bonds

- Physical Chemistry
- Intermolecular Forces: Van der Waals Force, Hydrogen Bond, Hydrophobic Effect
- What Difference LC/MS/MS and MS/MS? Principles and Protein Identification
- HPLC: Methods and Principles of Reversed-Phase Chromatography
- Mass Spectrometry: Molecular Weight and Mass Spectra in MS
- Fluorescence Spectra: Fluorescence Spectroscopy and Phosphorescence
- Raman Spectra: Energy of Raman Spectroscopy, Difference from IR Spectra
- IR Spectra (Infrared Absorption Spectra): Vibration and Fingerprint Area
- Absorbance of UV-Vis Absorption Spectrum: Beer–Lambert Law
- Column Chromatography: Separating Compounds and Determine the Developing Solvent
- Thin-Layer Chromatography (TLC): Principles, Rf values and Developing Solvent
- Adsorption Chromatography: Principles, Silica Gel Stationary Phase, and Interactions
- NMR Coupling of Benzene Rings: Ortho-Meta Peak and Chemical Shifts
- Principles of NMR: How to Read Spectra and Couplings

- Secondary Math
- Inscribed Angle Theorem: Central Angle and Arc Length
- Pythagorean Theorem: Formulas and Calculation Methods
- Midpoint Theorem and Similarity: Proofs, Converse, and Parallelogram Relationships
- Triangle Similarity in Math: Similarity Theorems, Proof and Similarity Ratio
- Parallelogram Definition, Theorem (Property) and Proof Problems
- Properties of Isosceles and Right Triangles: Congruence Theorems and Proof Problems
- Triangle Congruence Theorems: SSS, SAS, ASA, and AAS
- Sum of Interior Angles and Exterior Angles of Polygons: Triangles, Quadrilaterals, and Pentagons
- Vertical, Corresponding, and Alternate Angles: Why Angles are Equal and Proofs
- The Basics of a Solid of Revolution: Calculate the Volume and Surface Area
- The volume and Surface Area of a Sphere: Calculations in Math Using Formulas
- Volume and Surface Area of Pyramids and Cones: Formulas and Generatrix
- Surface Area of Prisms and Cylinders: Calculations and Formulas
- The Arc Length and the Sector Area: Circles and Arcs in Math
- Basics of Math Probability: Coins and Dice with a Tree Diagram
- Basics of Quadratic Functions: How to Solve Problems and Draw Graphs
- Quadratic Equations: Square Root, Factorization, and Quadratic Formula
- Square Root Addition and Subtraction: How to Calculate Fractions and Square Roots
- Rationalizing the Denominator: How to Eliminate the Square Root
- Multiply and Divide Square Root: How to Do Prime Factorization
- Basics of Square Root and Radical Symbol: Rational and Irrational Numbers
- How to Solve Linear Functions: Graph of Slope/Intercept and Intersection
- Simultaneous Equations: Addition Method and Substitution Method
- Direct and Inverse Proportion: Coordinates and Equations in Graphs
- Linear Equations: Transposition and Tips for Solving Word Problems
- Expansion by Factoring Formulas and Polynomial Factorization
- Multiply and Divide Polynomials, Distributive Property, and Substitutions
- Algebraic Expressions of Monomials and Polynomials: Addition and Subtraction
- Commutative Property and Associative Property: Addition and Multiplication in Math
- Four Arithmetic Operations of Positive and Negative Numbers: Priority of Math Calculations
- Positive and Negative Numbers: Multiplication, Division and Power
- Positive and Negative Numbers: Addition and Subtraction / Absolute Value

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