Organic Chemistry – Some Basic Principles and Techniques

In the molecule $CH_{2}=CH-CN$, what is the hybridization of the carbon atom in the nitrile ($-CN$) group?

Which type of orbital overlap results in the formation of a sigma ($\sigma$) bond?

Which of the following is NOT an organic compound according to modern definitions?

The carbon-carbon bond length is shortest in which of the following?

The 'Vital Force Theory' was successfully challenged in 1828 when Friedrich Wöhler synthesized urea, an organic compound, from an inorganic precursor. According to the reaction scheme shown below, identify the inorganic starting material 'X' that undergo thermal rearrangement to form urea.

Which of the following molecules has a linear geometry around the carbon atoms?

Which of the following features is NOT a characteristic of a homologous series?

In a bond-line representation, a 'vertex' or 'end' usually represents which group?

The formal charge on the central oxygen atom in the ozone molecule ($O_{3}$) is:

Which of the following organic compounds is purified by sublimation?

How many sigma bonds are present in ethyne ($HC\equiv CH$)?

Which orbital overlap is involved in the $C-C$ sigma bond of ethane?

The bond angle of $120^\circ$ is found in which hybridization?

Which of the following has a tetrahedral shape?

Which of the following contains zero $\pi$ bonds?

Which of the following molecules has a trigonal planar shape?

In the resonance structure of the acetate ion, the hybridization of the carboxylate carbon is:

Which of the following shows the correct relationship for the volume of hybrid orbitals?

The hybridization of Carbon in the free radical $\cdot CH_{3}$ is generally considered to be:

For the molecule $CH_{3}-CH_{2}-CH_{3}$, the $C-C-C$ bond angle is slightly greater than $109.5^{\circ}$ (about $112^{\circ}$). This is due to:

What is the molecular formula of Ethane?

Which of the following atoms must always be shown with its symbol in a bond-line formula?

How many $C-C$ single bonds are present in Propane?

The condensed formula for Ethanol is:

In the bond-line formula of phenol, how many $sp^2$ carbons and how many lone pairs on oxygen are present?

How many carbon atoms are $sp^3$ hybridized in the molecule $CH_2=CH-CH_2-C\equiv N$?

Which of the following is a representation of the allyl group?

How many tertiary ($3^\circ$) hydrogen atoms are present in the structure of $3-ethyl-2-methylpentane$?

The representation of $Allyl\ alcohol$ is $CH_2=CH-CH_2OH$. Identify the total number of $sp^3$ hybridized atoms in the molecule.

In the bond-line formula of $Cubane$ ($C_8H_8$), what is the hybridization of each carbon atom?

The term 'Aliphatic' was originally derived from the Greek word for:

Which of these is NOT a heteroatom in the context of heterocyclic organic chemistry?

Which of the following describes an unsaturated compound?

In the classification of organic compounds, what is a carbocyclic compound?

Organic compounds containing the carbonyl group ($>C=O$) can be classified into various derivatives based on the specific atom or group ($X$) attached to the carbonyl carbon ($R-CO-X$). According to the classification chart provided, which class of organic compounds is represented by the symbol '?'?

Biphenyl consists of two benzene rings joined by a single bond. How is it classified?

Which class of organic compounds is represented by the general formula $R-O-R'$?

A compound belongs to the homologous series of 'Alkyne' and contains 6 hydrogen atoms. How many carbon atoms does it have?

Which of the following aromatic compounds does NOT contain a benzene ring in its structure?

Identify the class of organic compounds having the general formula $R-\text{CO}-\text{NH}-R'$.

What is the IUPAC name for the compound $CH_{3}-CH_{2}-CH_{2}-F$?

What is the IUPAC name for the diene $CH_{2}=CH-CH=CH_{2}$?

What is the IUPAC name for $CH_{3}-CO-CH_{3}$?

Which suffix is used for a nitrile group ($C \equiv N$) where the carbon is part of the parent chain?

Identify the IUPAC name of the compound $CH_{3}-C(CH_{3})_{2}-CH_{2}-CH(CH_{3})_{2}$.

What is the IUPAC name for $CH_{3}-CH(NH_{2})-CH_{3}$?

Identify the IUPAC name for the diyne $CH_{3}-C\equiv C-C\equiv CH$.

Identify the IUPAC name for $CH_{3}-C(CH_{3})=CH-CHO$.

What is the IUPAC name of $CH_{3}-CO-CH_{2}-COOCH_{3}$?

The correct IUPAC name for $CH_{3}-CH(CH_{3})-CH_{2}-CH_{2}-Cl$ is:

Which of the following alkanes does not show isomerism?

Metamerism is most commonly observed in which of the following functional groups?

The total number of structural isomers possible for the molecular formula $C_3H_6O$ is (including aldehydes, ketones and alcohols/ethers with rings/unsaturation):

Which type of isomerism is represented by the movement of the double bond in the carbon chain?

Which of the following molecular formulas can represent both an alkene and a cycloalkane?

What is the relationship between $CH_3CH_2COOCH_3$ and $CH_3COOCH_2CH_3$?

Primary, secondary, and tertiary amines having the same molecular formula are:

A mixture of (R) and (S) enantiomers of a compound has an optical purity (enantiomeric excess) of 60%. If the mixture contains 10.0 g of the (R)-isomer, and the (R)-isomer is the major component, what is the total mass of the mixture?

For the molecular formula $C_4H_8O$, how many of the structural isomers are cyclic ethers? Use the classification in the diagram to help count the individual structures.

Consider the ketone 3-methylpentan-2-one. How many distinct enol forms, including all possible stereoisomers (geometrical and optical), can this compound theoretically exist as?

In hyperconjugation, which type of orbital overlap occurs between the $C-H$ sigma bond and the adjacent pi system?

Which effect explains why the $C-Cl$ bond in vinyl chloride is shorter than in ethyl chloride?

Which of the following species acts as a Lewis acid during an organic reaction?

Heterolytic fission of a $C-C$ bond is most likely to occur in which type of solvent?

During the addition of $H^+$ to an alkene, the pi electrons shift to the carbon where $H^+$ attaches. This is an example of:

Which effect is responsible for the acidity of chloroacetic acid being higher than acetic acid?

As the distance from the polar group increases in a carbon chain, the magnitude of the Inductive effect:

Which of the following will be the most stable radical?

The dipole moment of vinyl chloride is lower than that of methyl chloride. This is due to:

Which of the following species has the highest nucleophilicity?

Between the Inductive effect and the Resonance effect, which one is generally stronger and more dominant in determining reactivity?

Which property must resonance structures share?

The $C-Cl$ bond in methyl chloride is polar due to:

Which of the following groups increases electron density on the benzene ring through the Mesomeric effect?

In the study of electronic displacements, resonance structures (canonical forms) contribute differently to the resonance hybrid based on their stability. Consider the two resonance structures of the methyl acylium ion: Structure A ($CH_3-C^+=O$) and Structure B ($CH_3-C \equiv O^+$). Which of the following statements correctly evaluates their relative stability?

The inductive effect ($I$-effect) involves the displacement of sigma electrons along a saturated carbon chain. Considering the electronic nature of the following substituent groups, identify the correct decreasing order of their negative inductive ($-I$) effect.

In an aqueous solution, the basic strength of methyl-substituted amines follows the order: $(CH_3)_2NH > CH_3NH_2 > (CH_3)_3N > NH_3$. The low basicity of $(CH_3)_3N$ compared to $(CH_3)_2NH$ is primarily due to:

In which of the following molecules is the Inductive effect of the substituent 'D' (deuterium) compared with 'H' (hydrogen) correctly identified?

What happens to the basicity of aniline if a methoxy ($-OCH_{3}$) group is introduced at the para position?

The dipole moment of trans-1,2-dichloroethene is zero, while that of the cis-isomer is $1.9 \text{ D}$. If we replace the Cl atoms with $CH_{3}$ groups (2-butene), the trans-isomer still has a zero dipole moment. This proves that:

In the distillation of a mixture of water and ethanol, which component is collected first in the receiver?

For the crystallization of sugar, which solvent is generally used?

Which of the following is an example of a partition chromatography?

The phase that does not move in chromatography is called the:

An organic solid $S$ is contaminated with two types of impurities: $I_1$ (insoluble in solvent $Y$ at all temperatures) and $I_2$ (highly soluble in solvent $Y$ at both high and low temperatures). $S$ is soluble in $Y$ only at high temperatures. Based on the purification flowchart provided, which fraction contains the purified organic compound $S$?

Which of the following organic compounds is most likely to be purified by steam distillation?

In paper chromatography, the stationary phase is actually:

Which of the following organic compounds will typically have the lowest $R_f$ value on a silica gel TLC plate using a non-polar solvent like Petroleum Ether?

What is the primary role of the 'Fractionating Column' in the separation of two liquids with close boiling points?

If the distribution coefficient $K$ of a solute between ether and water is $3$ in favor of ether, what fraction of the solute remains in the water after one extraction with a volume of ether equal to the volume of water?

In the detection of carbon, the gas evolved is passed through lime water. What is the observed change?

Which of the following is NOT required for the qualitative analysis of elements in an organic compound using the sodium fusion method?

In the estimation of Phosphorus by weighing $Mg_2P_2O_7$, the 'magnesia mixture' consists of $MgCl_2$, $NH_4Cl$, and which other reagent?

Which element forms a yellow precipitate of silver halide that is insoluble in $NH_4OH$?

In the Liebig method, the increase in mass of the potash bulbs represents the mass of which substance?

In the detection of nitrogen, the formation of Prussian blue color is due to the reaction of $Fe^{3+}$ ions with which species?

Which of the following nitrogenous compounds will NOT give nitrogen gas in the Dumas method?

Which of the following statements is true for the 'Beilstein Test'?

Which of the following types of chromatography involves the separation of components of a mixture over a stationary liquid phase supported on an inert solid?

In the estimation of Carbon and Hydrogen, the $CO_2$ produced is absorbed in a bulb containing: