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Secondary structure of proteins

Introduction Proteins are polymers of amino acids and 20 different amino acids arranged in infinite patterns to form different types of proteins. Proteins are involved in different roles in the living organisms, from carrying out important cellular functions like metabolic reactions to being an important structural component of animals, human and plant body parts. Proteins … Read more

E-Z Nomenclature

Introduction to E-Z nomenclature E-Z notation is used to name geometric isomers. It is an extension of cis-trans isomer. When none or most of the groups attached to the double bond are not same then in IUPAC system geometric isomers are notified or named with E or Z. For the notification of this type of isomers … Read more


Isomerism Definition Compounds which have same molecular formula but differ in modes of combination or arrangement of atoms within the molecule are known as isomers and this phenomenon is know as isomerism. Isomers can have different physical or chemical properties. As for example, the cis and trans isomers of but-2-ene are as follows: Classification of … Read more

Organic Compounds

Organic Compounds Definition Organic compounds are a type chemical compounds where one or more than one carbon covalently bonded with each other and with other atom like nitrogen, oxygen, halogen etc. Such as, methane (CH4), ethane (C2H6), benzene (C6H6) etc. Exceptions Few carbon containing chemical compounds like metal cyanides (CN), oxides of carbon (CO2, CO), … Read more

Geometric Isomers

Geometric Isomers Definition Geometric isomerism is a kind of stereoisomerism. It is also known as cis-trans isomerism or E-Z isomerism. Geometric isomerism occurs due to the restricted rotation about carbon-carbon double bonds or carbon-carbon single bonds in cyclic compounds. Geometric isomers are the stereoisomers which differ from each other in the arrangement of groups with … Read more

Structural Isomers

Structural Isomers Definition Structural isomerism, or constitutional isomerism,  is a type of isomerism where isomers have same molecular formula but have different arrangements of atoms within the molecule. e.g. n-pentane, isopentane and neopentane are structural isomers. Types of isomerism Structural isomerism is of five types: Chain isomerism Position isomerism Functional group isomerism Metamerism Tautomerism 1. Chain isomerism … Read more