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Second order reaction – Let us take a second order reaction of the type 2A ⎯⎯→ products – Suppose the initial concentration of A is a moles liter–1. – If after time t, x moles of A have reacted, the concentration of A is (a – x). – We know …

Infrared Spectroscopy of Hydrocarbons – Hydrocarbons contain only carbon–carbon bonds and carbon–hydrogen bonds. – An infrared spectrum does not provide enough information to identify a structure conclusively (unless an authentic spectrum is available to compare “fingerprints”), but the absorptions of the carbon-carbon and carbon-hydrogen bonds can indicate the presence of …

First order reaction – Let us consider a first order reaction: A → products – Suppose that at the beginning of the reaction (t = 0), the concentration of A is a moles liter–1. – If after time t, x moles of A have changed, the concentration of A is …

– In this subject, we talk about how to Measure the IR Spectrum. Measurement of the IR Spectrum – Infrared spectra can be measured using liquid, solid, or gaseous samples that are placed in the beam of infrared light. – A drop of a liquid can be placed as a …

– In this subject we talk about Molecular Vibrations as introduction to understand IR spectrum Molecular Vibrations – Before discussing characteristic infrared absorptions, it’s helpful to understand some theory about the vibrational energies of molecules. – The following drawing shows how a covalent bond between two atoms acts like a …

– we will discuss the Molecularity of a reaction and the Differences Between Order and Molecularity. Molecularity of a reaction – Chemical reactions may be classed into two types : (a) Elementary reactions (b) Complex reactions – An elementary reaction is a simple reaction which occurs in a single step. …

Esters of Inorganic Acids – In addition to forming esters with carboxylic acids, alcohols form inorganic esters with inorganic acids such as nitric acid, sulfuric acid, and phosphoric acid. – In each type of ester, the alkoxy (-OR) group of the alcohol replaces a hydroxyl group of the acid, with …

The Sulphur system –  Sulphur system is a one-component, four-phase system. – The four phases are: (a) Two solid polymorphic forms : Rhombic Sulphur (SR) Monoclinic Sulphur (SM) (b) Sulphur Liquid (SL) (c) Sulphur Vapour (SV) – All the four phase can be represented by the only chemical individual (sulphur) …

– In this subject we will talk about the Esterification of Alcohols. What are Alcohols? – Alcohols are organic compounds containing hydroxyl (-OH) groups. – They are some of the most common and useful compounds in nature, in industry, and around the house. – The word alcohol is one of …

Unique Reactions of Diols – Unique Reactions of Diols are: (1) The Pinacol Rearrangement (2) Periodic Acid Cleavage of Glycols (1) The Pinacol Rearrangement – Using our knowledge of alcohol reactions, we can explain results that seem strange at first glance. – The following dehydration is an example of the …

Reactions of Alcohols with Thionyl Chloride – Reactions of Alcohols with Thionyl Chloride give alkyl chloride. – Thionyl chloride (SOCl2) is often the best reagent for converting an alcohol to an alkyl chloride. – The by-products (gaseous SO2 and HCl) leave the reaction mixture and ensure there can be no …

The Water system – Under normal conditions the Water system is a three-phase, one-component system. – The three phases involved are liquid water, ice, water vapour. – All these phases can be represented by one chemical entity H2O and hence one component of the system. – The number of phases …

Reaction of Alcohols with Phosphorus Halides – Reaction of Alcohols with Phosphorus Halides gives alkyl halides. – Several phosphorus halides are useful for converting alcohols to alkyl halides. – Phosphorus tribromide, phosphorus trichloride, and phosphorus pentachloride work well and are commercially available. 3 R-OH + PCl3 → 3 R-Cl + …

Polymorphism – The occurrence of the same substance in more than one crystalline forms is known as Polymorphism. – Polymorphism phenomenon is shown by both elements and compounds. In the case of elements the term allotropy is often used. – The individual crystalline forms of an element are referred to …

Phase Diagram – A phase diagram is a plot showing the conditions of pressure and temperature under which two or more physical states can exist together in a state of dynamic equilibrium. – The following figure is a typical phase diagram for a one-component system. – The diagram consists of …

– In this topic the Reactions of Alcohols with Hydrohalic Acids such as HBr , HCl are discussed Reactions of Alcohols with Hydrohalic Acids – Tosylation of an alcohol, followed by displacement of the tosylate by a halide ion, converts an alcohol to an alkyl halide. – This is not …

Derivation of the phase rule – Here the derivation of the phase rule for one-component system and two-component system are discussed. – Consider a heterogeneous system in equilibrium of C components in which P phases are present. – We have to determine the degrees of freedom of this system i.e., …

Degree of Freedom – The term Degree of Freedom represented by F in the phase Rule equation (F = C – P + 2) is defined as follows : the least number of variable factors (concentration, pressure and temperature) which must be specified so that the remaining variables are fixed …

The Phase Rule statement – The phase Rule is an important generalization dealing with the behaviour of heterogeneous systems. – In general it may be said that with the application of phase rule it is possible to predict qualitatively by means of a diagram the effect of changing pressure, temperature …

Alcohols as Nucleophiles and Electrophiles; Formation of Tosylates – One reason alcohols are such versatile chemical intermediates is that they react as both nucleophiles and electrophiles. – The following scheme shows an alcohol reacting as a weak nucleophile, bonding to a strong electrophile (in this case, a carbocation). – An …