The functional group overrides all of above rules since it has more priority than the double bonds, triple bonds, side chains and other substituents. While choosing the alphabetical order, the prefixes like di, tri, tetra must not be taken into account. -benzene. The triple bond gets the lower number. Monoatomic cations (positive) are named the same way as their element, and they come first when naming a compound. However the larger ring has more priority irrespective of its nature (whether It is added immediately after the root word. known as bridge head carbons. However the 2,7,8 is chosen since it has lowest number i.e., 2 on the first occasion of difference when compared with the other set: 3,4,9. Propan-1-ol, butan-1-amine, ethanoic acid, ethanoylchloride, butanamide If the suffix starts with a consonant or there are two or more of a functional group meaning di, or tri needs to be The first step in naming an organic compound is to select the parent chain and give the root word depending on the number of carbons in it. The number of methyl groups are indicated by di and tri in the following cases. and 1 carbon atoms connecting the two bridge head carbons. iv) If there are two or more same type of simple substituents they should be prefixed by di, tri, tetra, penta etc. The nomenclature of sulfides can be easily understood if one understands the nomenclature of the corresponding ethers. E.g. The numbering is done starting from skeletal carbon of small ring and They are of two types: Formed by replacing the hydrogen atom in the –COOH by some other radical, usually an alkyl or aryl radical forming an ester. However organic chemists realized the need for a systematic naming for organic compounds since a large number of organic compounds are synthesized in due course. For simplicity, we will use the term 'hydrocarbons' from here on out. Functional groups undergo the same chemical reactions no matter how large or small the molecule is. Functional groups are groups of atoms found within molecules that are involved in the chemical reactions characteristic of those molecules. In the phenylcycloheptane, the non-aromatic ring, cycloheptane is Therefore the double bond is to be given the lower number whenever both double bond and triple bond are at equivalent positions on the parent chain. Menu. In chemistry, a number of prefixes, suffixes and infixes are used to describe the type and position of the functional groups in the compound. Just carbon and hydrogen... no multiple bonds... saturated: single b…. The suffix -yl is used in organic chemistry to form names of radicals, either separate species (called free radicals) or chemically bonded parts of molecules (called moieties). rm_nevadale. E.g. It has more priority over multiple bonds also. iii) The numbers and letters are separated by hyphens. •When using a suffix, add in the following way : If the suffix starts with a vowel- remove the –e from the stem alkane name e.g. 7. In the following bicyclo compound, the methyl group is is considered E.g. "i" and not under "b" or "p". In the following molecule, 5-ethyl-2-methylheptane, the methyl and ethyl groups are not at equivalent positions. Home. These will be dealt at appropriate sections. The two words that put fear into many students. prefix. v) If the side chains themselves contain terms like di, tri, tetra etc., the multiplying prefixes like bis, tris, tetrakis etc., should be used. By using this system, it is possible to give a systematic name to an organic compound just by looking at its structure and it is also possible to write the structure of organic compound by following the IUPAC name for that compound. 3) If the molecule contains functional group or groups, a secondary suffix must be added to indicate the main functional group. The counting of carbons is done from the left hand side of the molecule. Again note that the 4-ene is written first. The But the position of double bond is shown by 2-ene. Organic Chemistry is the study of compounds based on hydrocarbons and their derivatives. For comments or suggestions please contact webmaster@acdlabs.com, R-3.1.4 Substituent prefix names for unsaturated/saturated parent hydrides. 1) The first step in giving IUPAC name to an organic compound is to select the parent chain and assign a root word. until the shortest bridge in finally numbered. below. How many carbons are there in the parent first point of difference, Compounds with The numbering is done starting from one of the bridge head carbon and Hence the root word is "hex-". 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. Where x and x' indicate the 2. E.g. E.g. In the following hydrocarbon, 6-methylhept-3-ene, the double bond is given the lower number and is indicated by the primary suffix 3-ene. There are The spiro compounds The infixes like cyclo, See explanation There are several to list, this has suffixes and prefixes for many organic compounds, also it'll let you decide the ones you need, List of different functional groups, categorised by similarities, i.e. continued until the spiro carbon. prefix may be added immediately before the root word or before the infix. But note that the ethyl group is written first in the name. The systematic IUPAC name of an organic compound consists of four parts. Hence the name is However the ethyl group comes first in the alphabetical order. Note: If there are two or more functional groups in a compound, the functional group with higher priority is to be selected as main functional group, which must be indicated by a secondary suffix. These numbers  In the following molecule, 4-ethyl-5-methyloctane, both methyl and ethyl groups are at equivalent positions. Note that in a polyatomic ion, the ion itself is held together by covalent bonds. in second ring. The final "-e" disappears if it is followed by another suffix that starts with a vowel. and substituents over the rings while counting this number. The complete systematic IUPAC name can be represented as: * The root word and 1osuffix together is known as base name. of compounds. They indicate the number of atoms in the bridges. In organic chemistry, a functional group is a set of atoms within molecules that function together to react in predictable ways. That is, alkan(e) \(+\) amide \(=\) alkanamide.A one-carbon chain is a carboxamide:. In the following bicyclo compound, there are three bridges with 2, 2 Note: The double bond has more priority than the triple bond. An alkyl group is a radical of with a certain number of carbons and is of the general formula C n H 2 n + 1 {\displaystyle {\text{C}}_{n}{\text{H}}_{2n+1}} that has had one of its hydrogens removed, freeing up one of its bonds. Yes. Also look at the alternate way of writing this molecule in which the ethyl groups are expanded to -CH2CH3. These numbers are arranged in the decreasing order number of atoms in the larger ring, excluding the spiroatom itself, are shown. Learn vocabulary, terms, and more with flashcards, games, and other study tools. this is more than suffice to all the students at various levels of their The IUPAC name of spiro compound has the infix "spiro" followed by square The suffix -oate is the IUPAC nomenclature used in organic chemistry to form names of compounds formed from carboxylic acids. carbons are not counted. Metric Prefixes. FDST 405 Final … In case of simple radicals, the group to be cited first in the name is decided by the alphabetical order of the first letter in case of simple radicals. This leads to setting up a system of nomenclature by  "International Union of Pure and Applied Chemistry, IUPAC" . On this page, I have given a logical introduction to IUPAC nomenclature. There is an alcohol group on 2nd Ions are atoms that have lost or gained electrons. Are there any side chains or substituents? IUPAC name when present in the compound. This is not an exhaustive reference to IUPAC nomenclature. vii) Nevertheless, the main functional group must be given the least number even though it violates the rule of first point of difference. carbons. * However the name of a complex radical is considered to begin with the first letter of its complete name. We should not compare 'e' in the word 'ethyl' and 'd' in the word 'dimethyl'. In the following hydrocarbon, hept-4-en-2-yne,  the double and triple bonds are not at equivalent positions. However the chain with more number of substituents (that with 3 substituents as shown in the following diagram) is to be taken as the parent chain. it is aromatic or not). suffix, "oic acid". (the prefixes for functional groups are already given). They have lower priority than double and triple bonds. * The "Bicyclo" infix is used to indicate the bicyclic nature of meth-eth-prop-but-1 … Here are ten practical tips … Notice that The IUPAC name is spiro[4.5]decane. Whereas the smaller ring is indicated by the Do not come under the impression that the ethyl groups (-C2H5) are side chains and the longest chain contains 5 carbons. The prefixes used for some common side chains and substituents are shown below. Actually the so called “Least Sum Rule” is the special case of above “Rule of First point of Difference”. -yne. The naming of compounds containing mainly carbon and hydrogen (organic compounds) is called organic nomenclature.In order to have a universal way to name organic compounds around the world, the International Union of Pure and Applied Chemists (IUPAC) wrote a set of rules and guidelines followed by all organic chemist.There are a lot of terms to know like, functional groups, suffixes … But the -COOH group has more priority than the -OH group. In the following examples, the old IUPAC system suggests different name when the acyclic chain contains more number of carbons than in cyclic system. In the second compound also the benzene ring is considered as substituent since it contains no functional group. to the locant of carbon in first ring and x' represents the locant of carbon i) The positions of double bonds or triple bonds or substituents or side chains or functional groups on the parent chain are to be indicated by appropriate numbers (or locants). the infix "bicyclo" if the compound is bicyclic. Acid Anhydride Definition in Chemistry. ; how to number the carbon atoms The following compound is considered as the derivative of cyclohexane. Also note that different suffix is used when carbon atom of the functional group is not part of the main chain. the same preference. It is to be selected as parent chain since it contains more carbons (7) than that containing double bond (only 6 carbons). This is optional and not necessary if the molecule contains no functional group. -ene. It is used to indicate the degree of saturation or unsaturation in the main chain. iv) The double bonds and triple bonds have more priority than the alkyl side chains and some other substituents like halo, nitro, alkoxy etc. E.g. The root word of the compound is based on the total number of skeletal carbons in the other, they are named as x,x'-bi(cycloalkyl). The suffix -ene is used in organic chemistry to form names of organic compounds where the -C=C- group has been attributed the highest priority according to the rules of organic nomenclature. View a full description and pricing on our web store. Even though two different series of locants are possible by numbering the carbon chain from either sides, the correct series is chosen by following the rule of first point of difference as stated below. E.g. learning curve. bicyclo[2.2.1]heptane. Jump to more examples iupac nomenclature of bicyclo compouns. and is indicated by the prefix, "hydroxy". Sometimes a number between hyphens is inserted before it to say that the double bond is between that atom and the atom with the next number up. iii) In the following molecule, there are three chains of equal length (7 carbons). E.g. Do not include the carbons in side chains or substituents over the rings while BIOC 831 Exam 4115 Terms. AP Chemistry Course and Exam Topics. vi) However, if the double and triple bonds are not at equivalent positions, then the positions are decided by the rule of first point of difference. Organic Chemistry Introduction. Study Flashcards On organic chemistry nomenclature prefix and suffix at Cram.com. Organic Chemistry – Study of Hydrocarbons & their derivatives. at least one carbon-carbon triple bond. A disulfide is a compound containing an -S-S- linkage. Find more examples on iupac names of cyclic compounds. When series of locants containing the same number of terms are compared term by term, that series which contains the lowest number on the occasion of the first difference is preferred. two cycles including the spiroatom. * The Prefix(es), infix and 2o suffix may or may not be required always. Hence when cyclic nucleus is attached to the non cyclic chain, it is always named as the derivative of the cyclic hydrocarbon irrespective of the length of the non cyclic chain. ii) Secondary suffix: It is used to indicate the main functional group in the organic compound and is added immediately after the 1 o suffix.. cyclic; or with the infix "spiro" if it is a spiro compound; or with The suffix is again divided into primary and secondary. The The prefix iso is used when the second carbon of the branched chain alkanes carries 1 methyl group while the prefix neo is used when second carbon of the branched chain alkanes carries 2 methyl group.. Types of carbon and hydrogen atoms in alkanes. However the Isobutyl and Isopropyl groups are alphabetized under For example, in the following molecule, the numbering can be done from either side of the chain to get two sets of locants. v) However, the longest chain must be selected as parent chain irrespective of whether it contains multiple bonds or not. This suffix was extracted from the word acetone.. It will decide the root word of the contain two cyclic rings that share one common carbon atom, which is called as the spiroatom. WRITING IUPAC NAME, Grammar to be followed in writing the IUPAC Organic chemistry. Monoatomic anions (negative) have the suffix -ide and come at the end of the compound's name.Notice that there is no need to write how many ions there are. 20 terms. Organic Chemistry Chapter 2: Alkane Prefixes. This is an organic chemistry glossary. suffix in the IUPAC name, whereas the remaining functional groups are considered as substituents and are indicated by the appropriate prefixes. Science, Tech, Math Science Math ... Organic Chemistry Prefixes and Suffixes. In the first compound as shown below, the acyclic chain is taken as parent chain since it has the -OH functional group on it. The chain (shaded) with 6 carbons that includes the -OH functional group is to be selected as parent chain irrespective of presence of another chain with 7 carbons that contains no functional group. The cyclopentane part is considered as substituent. concise and unified approach is followed to help in giving IUPAC names to almost all types Metric or SI (Le Système International d'Unités) prefix are based on powers … This is a very new IUPAC recommendation. Then the meth-eth-prop-but-(prefix) 1 carbon atom (prefix) 2 carbon atoms (prefix) 3 carbon atoms (prefix) 4 carbon atoms. The IUPAC name of the following compound is arrived in steps mentioned writing IUPAC names, Rule of Complex p chemical compounds include air within them. continued through the longest bridge until another bridge is reached. E.g. Next: R-3.1.2 Hydro prefixes R-3.1.3 Dehydro prefixes R-3.1.4 Substituent prefix names for unsaturated/saturated parent hydrides chain? Organic Chemistry Prefixes and Suffixes. the parent chain. ii) If two or more side chains are at equivalent positions, the one to be assigned the lower number is that cited first in the name. etc., in the Hence the name is 1.1'-bi(cyclopentyl). But organic chemistry, or the study of carbon-containing compounds, isn't so scary at all. But here’s the thing that’s often not mentioned: Organic chemistry is a subject that anyone can ace. While counting the number of E.g. "b". organic chemistry13 Terms. Whereas the -OH group is considered as substituent It is a streamlined version of our popular ACD/Name software. In the following case, “dimethylbutyl” is considered as a complete single substituent and is alphabetized under "d". E.g. The root word is vi) The chain with main functional group must be selected as parent chain even though it contains less number of carbons than any other chain without the main functional group. derived from the larger ring. But the chain with the a double bond as shown in the diagram (II) is to be selected as the parent chain. There is a methyl group on 3rd carbon. Functional groups can pertain to any molecules, but you will usually hear about them in the context of organic chemistry.The symbol R and R' refer to an attached hydrogen or hydrocarbon side chain or sometimes to any group of atoms. name, IUPAC The x refers * In case of simple radicals, they are alphabetized based on the first letter in the name of simple radical without multiplying prefixes. E.g. bicyclo compounds contain two fused rings with two connecting common carbon atoms In the earlier days, the conventional names for organic compounds were mainly derived from the source of occurrence. Hence this compound is named as the derivative of cycloheptane. Organic Chemistry: Functional Group Name Endings16 Terms. Hence it is considered as the main functional group and indicated by secondary We will discuss their general formula, physical and chemical properties. the functional groups. ii) The numbers are separated by commas. The prefix is used to indicate the side chains, substituents and low priority functional groups (which are considered as substituents). The carbon chain or In the following organic compound, 5-hydroxyhexanoic acid,  both -OH and -COOH groups are There are other situations which will decide the parent chain. i) In the following molecule, the longest chain has 6 carbons. However, according to the 1979 convention: “a hydrocarbon containing a small cyclic nucleus attached to a long chain is generally named as a derivative of the acyclic hydrocarbon; and a hydrocarbon containing a small group attached to a large cyclic nucleus is generally named as a derivative of the cyclic hydrocarbon.” Most of the textbooks and teachers still follow this convention. other. parent chain. Note: The groups: sec-butyl and tert-butyl are alphabetized under Here are some examples: Alkenes and Alkynes - unsaturated hydrocarbons Double bonds in hydrocarbons are indicated by replacing the suffix -ane with -ene.If there is more than one double bond, the suffix is expanded to include a prefix that indicates the number of double bonds present (-adiene, … E.g. The shaded part shows the longest chain that contains 7 carbons. The root word is benzene in the following compound. To have an chemical p using a polyatomic … 4) Prefix the root word with the infix "cyclo" if the parent chain is Hence, whenever there are two or more chains with equal number of carbons, the chain that contains double or triple bond is to be selected as the parent chain irrespective of other chain containing more number of substituents. The longest continuous carbon chain containing as many functional groups, double bonds, triple bonds, side chains and substituents as possible is to be selected as parent chain. Though looking simple, the least sum rule is valid only to chains with two substituents, a special case. Choose from 500 different sets of chemistry prefixes suffixes flashcards on Quizlet. The IUPAC name of bicyclic compound has the infix "bicyclo" iii) When two non-aromatic rings (alicyclic) are connected to each other, In the following molecule, the ethyl group is written first since the letter 'e' precedes the letter 'm' of methyl in the alphabetical order. E.g. IUPAC NOMENCLATURE OF ORGANIC COMPOUNDS | RULES, Steps involved in iv) The multiple bonds (double or triple bonds) have higher priority over alkyl or halo or nitro or alkoxy groups, and hence should be given lower numbers. Organic chemistry has a reputation for being a challenging course. Remember that the alkyl groups along with halo, nitro and alkoxy have These carbon-containing compounds have carbon and hydrogen atoms, so they are also referred to as hydrocarbons. There are two chains with 6 carbons. The root words used for different length of carbon chain (upto 20) are shown below. A (Organic) sulfides have the structure R-S-R′, and are therefore the sulfur analogues of ethers. are numbered. The smaller ring is indicated by the prefix: cyclopentyl. Learn chemistry prefixes suffixes with free interactive flashcards. square bracket. In this section of Some basic concepts of Organic Chemistry Class 11 NCERT Solutions, you would recall what is meant by the catenation of carbon elements and that this property is the reason why carbon forms covalent bonds with other elements. i) The IUPAC name of an alicyclic compound is prefixed with "cyclo". Therefore it is to be written first in the name and to be given the lowest number. Note: This is not the complete reference. Anyway, organic chemistry often sounds scary because all of the nomenclature, or naming, of all of the hydrocarbons. E.g. E.g. Doing well, though, requires working not only hard but also efficiently. iv) However if two alicyclic rings of same size are connected to each 7-7D Amides, \(RCONH_2\) 1. 2) Next, the appropriate primary suffix(es) must be added to the root word to indicate the saturation or unsaturation. This allows it to bond to a carbon (or oxygen, etc.) 2.2.1 ] heptane it to bond to a carbon ( or oxygen etc... 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Levels of their learning curve to each other atoms found within molecules that function to! Look at the root word to indicate the spiro carbon side of the bridge, the methyl is... Isobutyl and Isopropyl groups are alphabetized under `` d '' chain irrespective of its name... To state which atom the =O atom is attached to acyl group the... To more examples on IUPAC names to almost all types of compounds based on the letter. With halo, nitro and alkoxy have the same way as their element, and Alcohols spiro... Features for quick and simple generation of IUPAC names, and they come when! 12.1 General Introduction words used for some common side chains and substituents over the ring. Makeup the IUPAC name of an organic compound consists of four parts while deciding the positions we., 6-methylhept-3-ene, the longest bridge until another bridge is reached compound ( IB HL )... 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Or covalent bond connecting these bridge heads is considered as the main chain cycloheptane larger! A logical Introduction to IUPAC nomenclature considered to be selected as the main chain this process is continued until shortest! Period ( dot ) counting the number of skeletal carbon atoms known as base.. ( ii ) the aromatic rings have more preference over the rings are attached each! Therefore the sulfur analogues of ethers a bridge saturated organic chemistry suffixes single b… ) 1 7-7D Amides \... The groups: sec-butyl and tert-butyl are alphabetized under '' i '' and not necessary if the molecule the organic chemistry suffixes! Parent hydrides and unified approach is followed by another suffix that starts with a vowel arrived steps. Version ) offers a standardized set of atoms in the name if are. Positions, we will discuss their General formula, physical and chemical.. Hydrogen atoms, so they are cited in alphabetical order, the double.... Quick and simple generation of IUPAC names of compounds “Least Sum Rule” the... Suffix 3-ene more comple… Ions are atoms that have lost or gained.... Atom is attached to immediately before the root word of the IUPAC of. Above “Rule of first point of Difference” some Basic Principles and Techniques 12.1 General Introduction the source of.! Be given the lowest number & Suffixes by class of compound ( HL! The phenylcycloheptane, the double bond as shown below the sulfur analogues of ethers the infixes are some times as... Remember that the parent chain which are considered as substituent since it contains multiple bonds or not ) or!, R-3.1.4 substituent prefix names for organic compounds are characterized by their groups! The infix b '' of cyclic compounds prefixes for functional groups are groups of atoms within! The non-aromatic ring, cycloheptane is larger radical is considered to begin with the double. `` d '' substituents are shown below the second compound also the ring. 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Of skeletal carbon atoms in the organic compound and is indicated by di and tri in the following compound. Here ’ s the thing that ’ s the thing that ’ s often mentioned! Understood if one understands the nomenclature, or the study of compounds the hydrocarbons be easily understood if understands. Thing that ’ s the thing that ’ s often not mentioned: chemistry... Different sets of chemistry prefixes Suffixes flashcards on organic chemistry – study of hydrocarbons their... Words that put fear into many students considered as a complete single substituent and is immediately. Actually the so called “Least Sum Rule” is the study of compounds formed from carboxylic acids )... Carbons ) degree of saturation or unsaturation compound is arrived in steps mentioned below known as bridge head carbons that. First when naming a compound containing an -S-S- linkage assigning the systematic IUPAC name when present in the,... Priority are treated as substituents ) of all of the corresponding ethers subject that anyone can ace Introduction... Rings with two connecting common carbon atoms connecting the two cycles including the.... Spiro compounds contain two cyclic rings that share one common carbon atom of the IUPAC name the. Chains or substituents on the next page where x and x ' indicate the functional! The amide nitrogen is substituted with lower-ranking groups than the acyl group, the methyl group more. Prefixed with `` Cyclo '' infix is used when carbon atom, is... With 2, 2 and 1 carbon atoms and give the locants to the root or. Side chains or substituents on the total number of methyl groups are alphabetized based on hydrocarbons and their.! Present in the parent chain =O atom is attached to each other scary at all rings while counting this.. @ acdlabs.com, R-3.1.4 substituent prefix names for unsaturated/saturated parent hydrides is special. Name is bicyclo [ 2.2.1 ] heptane you will learn how to number the carbon (! Of atoms in the parent chain irrespective of its nature ( whether it contains bonds... The root word of the parent chain webmaster @ acdlabs.com, R-3.1.4 substituent prefix names unsaturated/saturated. Primary and secondary name to an organic compound, 5-hydroxyhexanoic acid, both methyl and ethyl groups ( )... Degree of saturation or unsaturation like di, tri, tetra must not taken! Of its complete name part of the hydrocarbon corresponding to the name and to selected. According to the name and to be given the lower number and is by! Is, alkan ( e ) \ ( RCONH_2\ ) 1 called the... Following rules are helpful in assigning the systematic IUPAC name to an organic compound is arrived steps! Word 'ethyl ' and 'd ' in the following spiro compound, there is one carbon atom which. Counting the number of skeletal carbon of small ring and continued until the spiro compound there... Numbering is done from the left hand side of the parent chain,. This organic chemistry note for IGCSE chemistry will cover the three major homologous series Alkane, Alkene, form... All the students at various levels of their learning curve called “Least Sum Rule” is the study of carbon-containing have! Ib HL chemistry ) -ane while counting the number of atoms found within molecules that are involved in following. Total number of skeletal carbons in side chains, substituents and are indicated by prefix. Always use `` the rule of first point of Difference” the saturation or unsaturation it! Substituent since it contains no double bond has more priority than the acyl group, the methyl group given...