HYDROCARBONS: NOMENCLATURE

Question 1

Composed wholly or especially coined or selected syllables

Answer 1

Systematic Name

Question 2

Refers to the structure of compounds

Answer 2

Systematic Name

Question 3

IUPAC Meaning

Answer 3

The International Union of Pure and Applied Chemistry

Question 4

A name no part of which is used in a systematic sense

Answer 4

Trivial Name

Question 5

Refers to compounds independent of structure and sometimes given before the structure is known

Answer 5

Trivial Name

Question 6

A name of which only a part is used in a systematic sense

Answer 6

Semisystematic-Semitrivial Name

Question 7

Under Organic Compounds

Answer 7

• Open-Chain / Aliphatic
• Closed Chain / Cyclic

Question 8

Under Closed Chain / Cyclic

Answer 8

• Homocyclic / Carbocyclic
• Heterocyclic

Question 9

Under Homocyclic / Carbocyclic

Answer 9

• Alicyclic
• Aromatic

Question 10

All organic compounds may be divided into two broad classes based upon the pattern of chain of carbon atoms.

Answer 10

• Open-chain or Aliphatic compounds
• Closed-chain or Cyclic compounde

Question 11

This class includes all hydrocarbons (saturated and unsaturated) and their derivatives which have open-chain structures.

Answer 11

Aliphatic Hydrocarbons

Question 12

Those which contain single bonds between all carbon atoms.

Answer 12

Saturated hydrocarbons

Question 13

On the other hand, unsaturated compounds contain a double (-C = C-) or a triple (-C = C-) bond between two carbon atoms.

Answer 13

Aliphatic Hydrocarbons

Question 14

These compounds have at least one ring (cyclic) system. These are further divided into two sub- classes: homocyclic and heterocyclic based on the atoms present in the ring. They are called homocyclic or carbocyclic when the ring is formed by carbon atoms only.

Answer 14

Cyclic Hydrocarbons

Question 15

Homocyclic (carbocyclic) compounds may again be divided into two groups namely :

Answer 15

• Alicyclic compounds
• Aromatic compounds

Question 16

This group includes saturated and I unsaturated cyclic hydrocarbons which resemble with the aliphatic hydrocarbons in properties.

Answer 16

Alicyclic Hydrocarbons

Question 17

The group of homocyclic compounds having special set of properties. They also have characteristic smell or aroma and hence called _______.

These include aromatic hydrocarbons and their derivatives are examples of such compounds.

Answer 17

Aromatic

Question 18

Alkanes Formula :

Answer 18

CnH2n+2

Question 19

Alkenes formula :

Answer 19

CnH2n

Question 20

Alkynes formula :

Answer 20

CnH2n-2

Question 21

In order to bring uniformity and rationality in naming the organic compounds throughout the world, International Union of Chemistry (in 1958) came out with a system of nomenclature later known as ?

Answer 21

IUPAC (International Union of Pure and Applied Chemistry) system.

Question 22

IUPAC was by

Answer 22

International Union of Chemistry (1958)

Question 23

The purpose of the IUPAC system of nomenclature is to establish an ____________ of naming compounds to facilitate communication.

Answer 23

international standard

Question 24

The goal of the system is to give each structure a unique and unambigous name, and to complete each name with a unique and unambigous structure.

Answer 24

IUPAC’s goal

Question 25

IUPAC nomenclature is based on naming molecule's ___________________ connected by single bonds either in chain or in ring.

Answer 25

longest chain of carbons

Question 26

Multiple bonds other than C and H, are indicated by ________ or ________ according to specific set of priorities.

Answer 26

prefixes or suffixes

Question 27

It indicates the number of carbon atoms in the longest possible continuous carbon chain also known as parent chain chosen by a set of rules. This is used for different length of carbon chain are shown below.

Answer 27

Root word

Question 28

It is used to indicate the degree of saturation or unsaturation in the main chain. It is added immediately after the root word.

Answer 28

Primary suffix

Question 29

It is used to indicate the main functional group in the organic compound and is added immediately after the 1º suffix.

Answer 29

Secondary suffix

Question 30

Denotes the numeral or letter that indicates the position of an atom or group in a molecule.

Answer 30

Locant

Question 31

Numerals is a locant when it indicates the position of a _________ or bond in a structure

Answer 31

substituents

Question 32

- separated by commas (e.g. 1,2,5,6-tetrabromocyclohexane), no space after the comma or colon - sets of numerals are joined by hyphen arranged in ascending order

Answer 32

Numerals

Question 33

Place as early in a name as to not cause confusion

Answer 33

Locant

Question 34

In branched chain hydrocarbons, one or more _____ groups are present as side chain attached to the main straight chain of carbon atoms.

Answer 34

alkyl groups

Question 35

The carbon atoms of the side chain constitute ______ groups.

Answer 35

alkyl groups

Question 36

The carbon atoms of the side chain constitute ______ groups.

Answer 36

alkyl groups

Question 37

These alkyl groups are written as ________ in the IUPAC name.

Answer 37

prefixes

Question 38

An alkyl group is obtained from an alkane by ________ one hydrogen atom.

Answer 38

removing

Question 39

Since the general formula of alkane is CnH2n+2, the general formula of alkyl group is _________.

Answer 39

CnH2n+1

Question 40

The ____________ are generally represented by R- and named by replacing the suffix -ane of the corresponding alkane by-yl.

Answer 40

alkyl groups

Question 41

Denotes number and identify attached groups.

Answer 41

Locant / Prefix

Question 42

Longest carbon chain

Answer 42

Root

Question 43

Functional class

Answer 43

Suffix / Ending