Organic Chemistry Basics MCQs 2026

A compound of carbon, hydrogen and oxygen with the -COOH group is a(n)

1. Aalcohol✓
2. Bcarboxylic acid✓
3. Chydrocarbon✓
4. Damine✓

The ability of carbon to bond with itself forming long chains is called

1. Aisomerism✓
2. Bhydrogenation✓
3. Cpolymerity✓
4. Dcatenation✓

The IUPAC name of the alkane with three carbons is

1. Aethane✓
2. Bmethane✓
3. Cpropane✓
4. Dbutane✓

The tetravalency of carbon allows it to form

1. Afour covalent bonds✓
2. Bone bond✓
3. Cionic bonds only✓
4. Dno bonds✓

Diamond and graphite are allotropes of

1. Asilicon✓
2. Bhydrogen✓
3. Coxygen✓
4. Dcarbon✓

Which of the following is an alcohol

1. Amethane✓
2. Bmethanol✓
3. Cmethanal✓
4. Dmethanoic acid✓

The suffix "-oic acid" in IUPAC naming indicates a

1. Acarboxylic acid✓
2. Balcohol✓
3. Cketone✓
4. Daldehyde✓

The reaction in which alkenes join into long chains called polymers is

1. Acombustion✓
2. Bneutralisation✓
3. Cpolymerisation✓
4. Dhydrogenation✓

The molecular formula of ethyne (acetylene) is

1. AC2H6✓
2. BC2H4✓
3. CCH4✓
4. DC2H2✓

The molecular formula of ethene is

1. AC2H6✓
2. BC2H4✓
3. CC2H2✓
4. DCH4✓

Benzene is an example of a(n) ___ hydrocarbon.

1. Asaturated straight-chain✓
2. Bsimple alkane✓
3. Caromatic✓
4. Dalkyne✓

The main constituent of natural gas is

1. Amethane✓
2. Bethene✓
3. Cethanol✓
4. Dbenzene✓

The IUPAC suffix used for alkenes is

1. A-ane✓
2. B-yne✓
3. C-ol✓
4. D-ene✓

The IUPAC suffix for alcohols is

1. A-ane✓
2. B-ene✓
3. C-ol✓
4. D-al✓

Fermentation of sugar by yeast mainly produces ethanol and

1. Aoxygen✓
2. Bcarbon dioxide✓
3. Chydrogen✓
4. Dmethane✓

The functional group present in ketones is

1. Aa carbonyl (C=O) between two carbons✓
2. B-OH✓
3. C-COOH✓
4. D-NH2✓

Which is an unsaturated hydrocarbon

1. Amethane✓
2. Bethane✓
3. Cpropane✓
4. Dethene✓

The IUPAC prefix for a chain of four carbon atoms is

1. Ameth-✓
2. Bprop-✓
3. Cbut-✓
4. Deth-✓

Complete combustion of hydrocarbons in plenty of oxygen produces carbon dioxide and

1. Awater✓
2. Bhydrogen✓
3. Cmethane✓
4. Dcarbon✓

The number of carbon atoms in propane is

1. A2✓
2. B3✓
3. C4✓
4. D5✓

Vinegar is a dilute solution of

1. Aethanol✓
2. Bmethanol✓
3. Cformic acid✓
4. Dacetic acid✓

The IUPAC name of CH3-CH3 is

1. Amethane✓
2. Bpropane✓
3. Cethane✓
4. Dbutane✓

Saturated compounds contain only ___ bonds between carbon atoms.

1. Adouble✓
2. Bsingle✓
3. Ctriple✓
4. Dionic✓

The process of adding hydrogen across a double bond is called

1. Ahydrogenation✓
2. Boxidation✓
3. Cneutralisation✓
4. Dfermentation✓

Compounds with the same molecular formula but different structures are called

1. Aisotopes✓
2. Ballotropes✓
3. Cpolymers✓
4. Disomers✓

Carbon has a valency of

1. A2✓
2. B4✓
3. C6✓
4. D1✓

Ethanol belongs to the family of

1. Aalkanes✓
2. Bacids✓
3. Calcohols✓
4. Desters✓

The -NH2 functional group is found in

1. Aalcohols✓
2. Bamines✓
3. Cacids✓
4. Dketones✓

The functional group of aldehydes is

1. A-CHO✓
2. B-OH✓
3. C-COOH✓
4. D-NH2✓

The functional group -COOH is characteristic of

1. Aalcohols✓
2. Bketones✓
3. Cesters✓
4. Dcarboxylic acids✓

The functional group -OH represents

1. Aan acid✓
2. Ban aldehyde✓
3. Can alcohol✓
4. Da ketone✓

A series of compounds with the same general formula differing by CH2 is a

1. Ahomologous series✓
2. Bperiodic group✓
3. Cisotope series✓
4. Dradical✓

The simplest alkyne, also called acetylene, is

1. Amethyne✓
2. Bethyne✓
3. Cpropyne✓
4. Dbutyne✓

The general formula of alkynes is

1. ACnH2n+2✓
2. BCnH2n✓
3. CCnHn✓
4. DCnH2n-2✓

Alkynes contain a carbon-carbon

1. Asingle bond✓
2. Bdouble bond✓
3. Ctriple bond✓
4. Dionic bond✓

The simplest alkene is

1. Aethene✓
2. Bmethene✓
3. Cpropene✓
4. Dbutene✓

The general formula of alkenes is

1. ACnH2n+2✓
2. BCnH2n✓
3. CCnH2n-2✓
4. DCnHn✓

Alkenes contain at least one carbon-carbon

1. Asingle bond✓
2. Btriple bond only✓
3. Cionic bond✓
4. Ddouble bond✓

The molecular formula of methane is

1. AC2H6✓
2. BC2H4✓
3. CCH2✓
4. DCH4✓

The simplest alkane is

1. Aethane✓
2. Bmethane✓
3. Cpropane✓
4. Dbutane✓

The general formula of alkanes is

1. ACnH2n+2✓
2. BCnH2n✓
3. CCnH2n-2✓
4. DCnHn✓

Alkanes are ___ hydrocarbons.

1. Aunsaturated✓
2. Baromatic✓
3. Csaturated✓
4. Dcyclic only✓

Hydrocarbons are compounds containing only carbon and

1. Aoxygen✓
2. Bnitrogen✓
3. Chydrogen✓
4. Dchlorine✓

The element that forms the backbone of all organic compounds is

1. Acarbon✓
2. Bhydrogen✓
3. Csulfur✓
4. Diron✓

Organic chemistry is mainly the study of compounds of

1. Anitrogen✓
2. Boxygen✓
3. Csilicon✓
4. Dcarbon✓