Organic Chemistry - Drawing Structures, Concepts, and Examples

Learn Markovnikov's Rule: definition, carbocation mechanism, HBr examples, and anti-Markovnikov addition with peroxides. Complete 2026 chemistry guide.

Understanding the failure of Benzene to undergo an Iodination reaction requires insight into multiple aspects of the reaction mechanism and the nature of the reactants.

In the carbon-halogen covalent bond, the halogen due to its higher electronegativity pulls the electrons in t

Friedel Craft acylation reaction is a type of electrophilic aromatic substitution reaction wherein the hydrogen of the aromatic ring is substituted with the acyl gr

Atom vs Element vs Molecule vs Compound: Clear comparison of these key chemistry terms, with examples

This article covers about the requirements for an ionic bond formation from the perspective of the electronegativity difference between atoms, and their ease of formation of ions.

This article covers about the requirements for an ionic bond formation from the perspective of the electronegativity difference between atoms, and their ease of formation of ions.

This article covers the basics of ionic compound formation.

Learning Objective: To learn about the atomic mass number using protons and neutrons.

Learning Objective: To learn about the components of an atom and the importance of proton numbers. 

Learning Objective: To learn about the size and composition of an atom. 

Learning Objective: To learn about tautomerism, a subtype of structural isomerism. 

Learning Objective: To learn about metamerism, a subtype of structural isomerism. 

Learning Objective: To learn about functional isomerism, a subtype of structural isomerism. 

Learning Objective: To learn about ring–chain isomerism, a subtype of structural isomerism. 

Learning Objective: To learn about positional isomerism, a subtype of structural isomerism. 

Learning Objective: To learn about chain or nuclear isomerism, a subtype of structural isomerism. 

If you look at the shape of s and p orbitals before hybridization, you will notice that - 

• The s orbital is spherical.

Learning Objective: To learn what is structural isomerism and its subtypes. 

Learning Objective: To calculate the number of active hydrogen bonds per molecule and techniques for detecting hydrogen bonds. 

Learning Objective: To learn about the impact Hydrogen bonding has on the physical properties of melting/boiling points, state, solubility, and reac

Learning Objective: To learn about different factors affecting hydrogen bond strength.

Learning Objective: To learn how an ion can amplify polarity in polar molecules.

Learning Objective: To learn about the factors affecting ion-induced dipole interaction strength.

Learning Objective: To learn about the ion-induced dipole interactions, their strength, and their occurrence.

Learning Objective: To learn with examples the application of ion-dipole interactions in our daily lives.

Learning Objective: To learn about the factors affecting ion-dipole interaction strength.

Learning Objective: To study how ionic solids and dipoles of polar liquids interact and their strength.

Learning Objective: To study how molecular weight, molecular shape, functional group, and carbon number impact density.

Learning Objective: To study which intermolecular forces and structural features affect the solubility of organic compounds in water. 

Learning Objective: To investigate which intermolecular forces are predominant in a liquid state and to study the impact of molecular weight, molecu

Learning Objective: To study the impact of symmetry, carbon numbers, geometry, and polarity on the melting point of solids.

Learning Objective: To learn about the intermolecular forces and how they impact an organic compound's physical properties.

Learning Objective: To learn about a few common reactions that carbon-centered free radicals undergo in organic chemistry.

Learning Objective: To learn the two different ways a free radical reacts and the mechanism it undergoes.

Learning Objective: To learn how to predict the stability of a hydrocarbon to form a free radical using the dissociation energy value of the C-H bon

Learning Objective: To study the structural features that contribute to the stability of a carbon-centered free radical in organic chemistry. 

Learning Objective: To study the structural features of a carbon-centered free radical in organic chemistry. 

Learning Objective: To learn about different ways by which the formation of a carbon-centred free radical occurs.

Learning Objective: To learn about various methods by which a carbanion reacts with other positive centers in organic chemical reactions.

Learning Objective: To compare different molecular structures with their pKa values to understand which structures can easily form and effectively s

Learning Objective: To learn different methods to stabilize a carbanion.

Learning Objective: To learn about the three ways carbanion intermediates are generated.

Learning Objective: To learn about the structure, type, and nature of the carbanion intermediate part of organic chemistry reactions.

Learning Objective: To understand the four common organic reactions that generate carbocation intermediates.

Skill Level - Intermediate

Learning Objective: To study the fate of a carbocation intermediate in a chemical reaction.

Learning Objective: To learn about the structural feature that stabilizes also destabilizes the carbocation intermediate.

Learning Objective: To study the two methods of how carbocation forms.

Skill Level - Intermediate

Learning Objective: To study carbocation as the reactive intermediate - formation, structure, and types.

Learning Objective: To study what reactive intermediates are, their types, and their role in organic chemistry.

Learning Objective: To learn through an example how a reaction outcome depends on the conformation of the reactant.

Skill Level - Intermediate

Learning Objective: To study the role of solvents in conformational isomerism.

Skill Level - Intermediate

Learning Objective: To understand the conformations molecules containing lone pair(s) mostly adopt.

Skill Level - Intermediate

Learning Objective: To study the importance of conformational analysis in organic chemistry. 

Skill Level - Intermediate

Learning Objective: To study the various stabilizing and destabilizing interactions affecting the stability of conformations. 

Learning Objective: To study the various terminologies for single-bond and double-bond-containing molecular conformations. 

Learning Objective: To study the common names of open-chain and closed-chain conformations and their stability. 

Learning Objective: To learn the various methods used to draw conformational isomers.   

Skill Level - Beginner

Learning Objective: To get familiar with conformational isomerism, what it means, how it occurs, and also differs from other forms of isomerism.   

Learning Objective: To study the ambident nucleophiles and how and from which end they attack the substrates to undergo chemical reactions.

Learning Objective: To study the three types of addition reactions that nucleophiles undergo.

Skill Level - Intermediate

Learning Objective: To study the three broad types of displacement reactions that nucleophiles undergo.

Learning Objective: To learn about the trend and order of nucleophilicity for the p-block elements in the periodic table

Learning Objective: To study the nucleophiles that function as sigma bond donors that form Carbon, Hydrogen, and Halogen bonds with the substrate.

Learning Objective: To study the behavior of pi bonds containing nucleophiles seen in organic chemistry reactions.

Learning Objective: To study the types of nucleophiles commonly encountered in organic chemistry and their behavior in a chemical reaction.

Learning Objective: To study the formation and different categories of electrophiles commonly seen in organic chemistry. 

Learning Objective: To study the various examples of organic reactions where the leaving group departs from a molecule and also understand its vario

Learning Objective: To compare various groups on their ability to break off or 'leave'

14 chapters, 300+ topics — browse the full course outline for CurlyArrows' Organic Chemistry Fundamentals. Free previews available.

Learning Objective: To study lone pair's role in chemical reactions as electron donors.

Learning Objective: To study the impact of lone pair on a molecule's polarity and dipole moment. 

Learning Objective: To study how the presence of a lone pair on the central atom of a molecule contributes to Hydrogen bonding, a type of intermolecular

Learning Objective: To investigate how the presence of a lone pair in a molecule affects its bond angle and, therefore, affects its shape.

Hills Nomenclature, also known as the Hills System or Hills notation, is a guideline for writing any chemical compound's empirical or molecular formula.

The very premise of a covalent bond is electron sharing.

August Kekulé (1866) was the first to propose the alternating single and double bond structure of benzene that can only be possible if carbon could join other carbon atoms and form a ring.

The first time the use of two dots or a colon (:) to represent two electrons acting as connecting links between the two atoms was proposed by G.N. Lewis in 1916.

Organic compounds in which carbon atoms are joined in a ring, unlike the open-chain counterparts, are represented using the polygon formula.

Molecular models are tools used for classroom or research to visualize better and interpret three-dimensional structures of organic molecules.

What is a Bond-Line or Skeletal Formula?

Carbon and Hydrogen containing bonds are chemically inert; still, they form the backbone of many organic compounds.

Certain conventions are used to represent three-dimensional structures of organic molecules on paper.

What is a Condensed Structural Formula?

The condensed structural formula provides the shortest way to understand the atoms and their numbers, their connection with respect to each other, an

Learning Objective: To study the octet rule by G.N. Lewis, considering both ionic and covalent bonding, with examples.

In his landmark paper, 'The Atom and the Molecule,' G.N. Lewis attempted to describe linkages between the atoms to understand the nature of covalent bonds.

Learning Objective: To study the limitations of the octet rule, with examples.

Carbon is naturally inclined to form new bonds, and in this quest, it may break away from the old ones.

Covered in this article are two types of curved (curly arrows), fish-hook and double-headed. We have included examples that reveal how to read the electron flow in reactions. The electron source can be a lone pair, charges, or a bond.

This article covers the introduction, formation, and characteristics of the ionic bond.

Learning Objective: To study with examples the hydrogen bond donors and acceptors.

Oxidation-Reduction Reaction in Organic versus Inorganic Chemistry

Inorganic chemistry describes oxidation in two ways.

In substitution reactions, an atom or group of atoms is displaced and replaced by another atom or group of atoms. The displaced atom is called the leaving group.

Elimination reaction involves the loss of two groups and the formation of a new bond.

A decomposition reaction breaks down the substrate into two or more smaller, simpler molecules.

An atom or group of atoms migrate from one position to another; such reactions are rearrangement reactions.

Two molecules combine in an addition reaction to form a single addition product (an adduct). The addition occurs in unsaturated molecules of alkenes (C=C), alkynes (C≡C), carbonyls (C=O), and imines (C=N). There are four mechanisms in addition type of reactions- Electrophilic addition, Nucleophilic addition, Free radical addition and Simultaneous addition (Pericyclic).

Learning Objective: To study the history, nature, examples, and types of free radicals, a reactive intermediate in organic chemistry.

Learning Objective: To learn about the average atomic mass and how to calculate it from its isotopic mass and natural abundance.
 

Dalton, in 1804, in his work on ‘Atomic Theory,’ proposed the law of chemical combination to explain how atoms form compounds.

Learning Objective: To study Vander Waals Debye force, interactions, and the factors affecting their strength. 

Learning Objective: To study Vander Waals Keesom's force, interactions, and strength. 

Learning Objective: Study Vander Waals London forces, interactions, and strength. 

The atoms that form covalent bonds are the nonmetals (p-block elements), and they must have an electronegativity difference lower than 1.7.

Once each electron of the two atoms forms the covalent bond, the electrons are simultaneously distributed between them so that they belong to both the at

Once the outermost valence electrons of the atoms are engaged in the covalent bond formation to make a molecule, some electrons withhold themselves from the bond-making p

The atoms that embark on the journey of bond formation are likely to have an electron imbalance. They are less stable and become highly reactive.

The Covalent bond is one of the two linkages by which atoms join to form molecules and is therefore classified under chemical bonds.

Pre-Requisite Reading: Lewis Structures, Types of reactions, Using curly arrows for electron movement, Identifying Functional groups. 

1) Alkylation

Branched alkyl chlorides (2⁰ or 3^o) cannot be used as a reagent in FC acylation reaction.

In this article we cover what is an inductive effect, how it occurs, two types of inductive effect with their examples, and finally how to represent an inductive effect on paper.

The stability order of different alkene substitution patterns is measured by comparing their heat of hydrogenations (denoted as ∆H^o) in kJ/mole or kcal/mol.

Alkene is a double bond containing hydrocarbon compound.

Alkenes are double bonds containing molecules. These double bonds are called pie bonds and are made up of two electrons.

Sharing resources is essential to build a harmonious world. When the resources are shared ineffectively conflicts emerges.

Electrophiles love electrons, and without them, they become unstable.

Pre-requisite: Nuclear charge, Valence electrons

This section mainly introduces Hydrogen bond interaction, how to visualize a hydrogen bond, how it occurs, and a few examples of molecules that show Hydrogen bonding.

Organic chemistry and human beings both pursue betterment and advancement.

What is a Lone Pair?

Lone pair is a set of electrons present in an atom’

A comprehensive list of 18 types of the arrows frequently encountered in chemistry with examples - Chemical Reaction Arrow, Reversible Reaction Arrow, Equilibrium Reaction Arrow, Double Headed Curly Arrow, Fishhook Curly Arrow, Dashed Arrow, The Crossed or The Broken Arrow, Resonance Arrow, Retrosynthesis Arrow, Rearrangement Reaction arrow, Reflux Reaction Arrow, Orbital Electrons Arrow, Co-ordinate Covalent Bond Arrow, Upward Arrow (Gas Evolution), Downward Arrow (Precipitate), Clockwise and Anti-Clockwise/ Stereochemical Arrow, Wavy Arrow, and Dipole Moment Arrow.

Learning Objective: To study what Van Der Waal forces are in chemistry and their example.

The Hydrogens attached to a Carbon atom are said to be equivalent if they are in a same chemical environment.

The DBE calculation uses the general molecular formula to find the presence of unsaturation in a compound. The unsaturation is calculated in levels or degrees. 

A halogen derivative of an alkane is called a Haloalkane, where the hydrogen is replaced with a halogen.

The three common hybridization states are - sp³, sp², and sp.

A Haloalkane is the Halogen derivative of an alkane obtained by replacing of one or more hydrogen atoms.

The nomenclature is mainly used for sp³ hybridized Carbon of an alkane.

Lattice points are the positions an atom, ion, or molecule can occupy in a crystal giving it its shape and charact

The Lewis dot structures are used to show the shared electron pairs between the bonded atoms in the molecule and the lone pairs of electrons if any.

The ylide is an electrically neutral molecule that has a negative carbon with an unshared electron pair (usually a carbanion) adjacent to a positive heteroatom (typically

Commonly, it is accepted that a compound is an Arrhenius acid if it liberates hydrogen ions as H⁺ in water. In the next step, these

Structural formulas are used to display covalently bonded molecules in the order they are bonded. The atoms may bond using single, double, or triple bonds.

Atoms generally form bonding arrangements that give them filled shells of electrons like a noble gas configuration.

A dihedral angle is obtained when two planes pass through three atoms and two bonds, of which one bond is common to both planes. 

Organic chemistry is a branch of chemistry that studies transformations at three levels- macroscopic (visual changes like rotting of an apple), m

A benzyl, abbreviated as Bn, refers to the phenylmethyl group (C₆H₅-CH₂-), consisting of a benzene ring attached to a me

Russian chemist Vladimir Markovnikov proposed Markovnikov’s rule in 1869 to predict the regiochemistry of addition reactions between unsymmetrical alkenes/ alkynes

The discovery of isomerism marked the advent of structural chemistry, where it became significantly important to establish structural formulas, welcome the abundance of structurally diverse compoun

Around the early 1800s, scientists began to notice the presence of isomerism in all types of compounds; however, at the time, it was referred to using different names.

Draw complete structural formulas and  condensed structural formulas for

Nucleophiles are electron-rich species that can donate a pair of electrons and form a new covalent bond with an electron-deficient counterpart called the

While nucleophiles donate two electrons in exchange for forming two-electron covalent bonds with the electrophiles, the negative charge due to the two ele

Following the footsteps of Gilbert N. Lewis in understanding the nature of the covalent bond, Linus N. Pauling stumbled upon an interesting observation.

If only valence shells participate in bonding reactions, then Carbon should only form two bonds using its two unpaired electrons. However, Carbon forms four bonds, as seen in CH4, CH3X, H2C=O, and O=C=O molecules. This discrepancy between the number of valence electrons of an atom and the number of bonds it forms (valency) is explained by the hybridization concept, an extension of the Valence Bond (VB) Theory.

The bond angle is the angle at which two adjacent bonds converge and meet at the central ato

An important thing about an atom is that it is made of three main components- pro

The longest carbon chain is the parent chain containing the principal functional group. 

IUPAC, an international body engaged in developing standards for naming chemical elements and compounds, has laid several rules known as 'IUPAC rules' to

Organic compounds predominantly consist of Carbon and Hydrogen atoms, also known as hydrocarbons.

Radical initiators are chemical species that quickly produce free radicals by light and heat exposure.

A radical reaction usually happens in three steps- Initiation (creation of free radicals), Propagation (multiplication and growth of radical reaction), and Termination (sto

Free radicals are generated due to the homolytic bond cleavage, a type of bond breaking where each atom holding the two-electron covalent bond gets one electron.

A carbocation is a positively charged, electron-deficient ion of carbon with only 6 valence electrons from the preferred 8 for covalent bonding.

A carbocation is a positively charged, electron-deficient carbon ion that acts as a reactive intermediate in many organic reactions.

A carbocation is a reactive intermediate with only 6 valence

A carbocation is a positively charged, electron-deficient carbon atom that acts as a reactive intermediate in many organic reactions.

In ionic compounds, a metal atom loses an electron, forms a cation, and another nonmetal atom gains it, creating an anion.

Metallic solid consists of several metal atoms of the same kind bonded together closely.

Several characteristic properties of the metals are due to the nature of the metallic bond. Some unique properties include- 

A metallic bond is a chemical bond seen in metals consisting of tightly bound metal atoms of the same type. 

Van der Waal’s interactions are the weak intermolecular forces of interactions.

Debye intermolecular forces of attraction occur between polar and nonpolar atoms or molecules.

Debye intermolecular forces of attraction occur between polar and nonpolar atoms or molecules.

If the size of a nonpolar atom is greater, it means that the atom has a higher number of electron containing orbitals.

Debye interactions require polar molecules to show polar-nonpolar type of intermolecular attractive interactions.

The strength of polar-nonpolar interactions is affected by the atomic size of the nonpolar atom (or molecule) and the electronegativity of the polar molecule. 

A polar molecule has natural poles. Therefore, when next to a nonpolar molecule, it will try to magnetize it temporarily. 

London dispersion forces are weak intermolecular forces found in all atoms and molecules.

London Dispersion forces are seen in all the atoms and the molecules; however, it is the exclusive force binding nonpolar molecules.

All atoms and molecules show London Dispersion Force, a primary way atoms and molecules interact.

A nonpolar molecule is made of two or more atoms where the electronegativity difference between the atoms is less than 0.5.

London dispersion force is the weakest of the three van Der

London dispersion forces are the weakest intermolecular forc

Hydrogen bonding is a type of electrostatic interaction occurring in mole

Keesom forces occur in polar molecules where the atoms have a considera

Polar molecules show Keesom forces.

A molecule is said to be polar if the bond electrons between the atoms in a covalent bond are unequally distributed, creating two ends.

There are three types of Van der Waal’s forces: Keesom Forces, Debye forces, and Lon

The van der Waal forces of interactions are weak intermolecular forces. For the atoms or molecules show these interactions only under certain conditions -

There are three types of Van der Waal’s force- Keesom Forces,

Van der Waals forces are weak intermolecular attractive forces that occur in polar and nonpolar atoms or molecules due to the shift in their electron pos

Van Der Waals forces are weak intermolecular attractive forces that hold closely various atoms and molecules without any physical linkage or bond. 

The atoms or group of atoms are classified based on the Inductive effect as electro

Inductive, along with resonance effects, are permanent effec

Water at room temperature is liquid in nature due to the hydrogen bonds holding the water molecules (H₂O).

A covalent bond holding two atoms is made of two electrons.

A chemical bond strength is a force holding the atoms in a bond, and separating such atoms requires energy input.

Among the isomeric alkanes of molecular formula C5H12, identify the one that on photochemical chlorination yields

i) A single monochloride

ii) Three isomeric monochlorides

An Organic Compound 'A' molecular formula C₈H₁₆O₂ was hydrolyzed with dilute H₂SO₄ to give a carboxylic acid 'B' a

In the presence of moisture, PCl₃ undergoes hydrolysis to release fumes of HCl gas.

We have subjected benzoic acid to Friedel Craft Acylation and Friedel Craft Alkylation Reactions as a substrate and as a reagent to fully understand the specific scenario when it does not undergo Friedel Craft Reactions.

Accidental discoveries and insatiable curiosity fuel chemistry. 

A compound containing carbon, hydrogen, and oxygen gave the following analytical data:

C = 40% and H = 6.67%

Calculate the molecular formula of the compound i

On analysis, a substance was found to have the following percentage composition:

K = 31.84, Cl= 28.98 and O = 39.18

Calculate its molecular formula if its mol

A salt containing water of crystallization gave the following percentage composition :

Mg = 9.76 ; S = 13.01 ; O =

2.746 g of a compound gave on analysis 1.94 g of silver, 0.268 g of sulphur, and 0.538 g of oxygen. Calculate the empirical formula of the compound.

An oxide of Nitrogen has the percentage composition : N = 25.94 and O = 74.06.

A compound was discovered to contain 32.65 % sulphur, 65.31 % oxygen, and 2.04 % hydrogen.

Q) How many valence electrons do the following elements have -

a) Carbon and Silicon 

b) Nitrogen and Phosphorus 

c) Oxygen and sulfur 

Question- Chlorine has two isotopes,³⁵Cl and ³⁷Cl; 75.77 % of chlorine is 35Cl, and 24.23% is 37Cl.

Question- How many protons and electrons do the following species have? 

Na+ (atomic number Z=11), Ar (atomic number Z=18), Cl- (atomic number Z=17)

Calculate number of protons and neutrons from isotopes of Oxygen ¹⁶O, ¹⁷O, and ¹⁸O.

Question: Nitrogen (Atomic Number 7) has stable isotopes (half-life greater than 1 sec) of mass numbers 13, 14, 15, 16 and 17.  Calculate number of protons and neutrons in each of the isotope

A hydrocarbon C₅H₁₀ does not react with Chlorine in dark but it gives a single monochlorocompound C₅H₉Cl in bright sunlight.

The electronic configuration of two elements A and B are -

A- 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

Question- An organic compound X contains 70% Carbon, 11.33% Hydrogen and 18.67% Oxygen. The molecular weight of the compound is 86.

The oxidation number of Phosphorus (P) is the unknown here. Let us consider it as x.

The Oxidation Number of Hydrogen (H) is + 1