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An inorganic/organic compound can work as an oxidizing agent for an organic compound. Depending on the substrate, an oxidant may produce an alcohol/aldehyde/epoxide, a carboxylic acid/diol/ketone, among many others. Chemoselectivity and stereochemistry are observed as well. Question: Click/tap to enlarge the image Solution infographic: Click/tap to enlarge the image MMPP = Magnesium monoperoxyphthalate, E + = Electrophile Outguessing oxidizing agent❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Ncert. Chemistry : Textbook for Class XI - Part.II ; National Council Of Educational Research And Training: New Delhi. (2)     Brown, C.; Ford, M. Higher Level Chemistry , 2nd ed.; Pearson Education: Harlow, Essex, 2014. (3)      Graham, T. W.; Fryhle, C. B.; Snyder, S. A. Organic Chemistry. ; Hoboken, Nj John Wiley Et Sons, Inc, 2016. (4)      Chouhan, M. S....

In thermodynamics the reference is the internal energy (in chemistry). The internal energy of a thermodynamic system is the energy of the system as a state function, measured as the amount of energy required to bring the system from its standard internal state to its internal state of interest. Anything that increases internal energy is positive and that decreases internal energy is negative. The first law of thermodynamics states that, when energy passes into or out of a system (as work, heat, or matter), the system's internal energy changes in accordance with the law of conservation of energy. Question: An ideal gas is taken through the cycle A  →  B  →  C  →  A as shown in figure. If the net heat supplied to the gas in cycle is 5 J , calculate the work done by the gas in the process C  →  A . Click/tap to enlarge the image Solution: Click/tap to enlarge the image q = Heat, w = Work done , ΔU = Change in internal energy Tantalizing thermodyn...

Close-packing of spheres in geometry is a dense, infinite, regular arrangement of congruent, identical spheres in an arrangement ( aka lattice). The cubic (or isometric) crystal system in crystallography is a crystal system where the unit cell is in the shape of a cube, one of the most common and simplest shapes found in crystals and minerals. One of the three main varieties of these crystals is body-centered cubic ( cI  or bcc ). Question: Determine the density of the Sodium metal ( bcc type). Atomic radius of Sodium = 1.6 x 10 –10 m . Solution: Click/tap to enlarge the image r = Atomic radius, a = Unit cell length, d = Density, Z = Lattice point, M = Molar mass, N = Avogadro number Sassy solid state❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Wikipedia Contributors. Cubic crystal system . Wikipedia. https://en.wikipedia.org/wiki/Cubic_crystal_system. ‌(2)     Ncert. Chemistr...

Enantiomers ( aka optical isomer, antipode, or optical antipode) are non-superimposable mirror images of a pair of molecular entities in stereochemistry. For the  Fischer projection formula for, say, ( S )-2-Chlorobutane, a 180º rotation in the plane of the paper (or screen) does not convert the structure to the ( R )-enantiomer, but flipping the structure over (a 180º rotation out of the plane), or exchanging the two vertical substituents ( i.e., top and bottom), or exchanging the two horizontal substituents ( i.e., right and left) does. Diastereomers aka diastereoisomers occur when two or more stereoisomers ( SIs ) of a compound have different configurations at one or more (but not all) of the equivalent (related) stereocenters and are not mirror images of each other. A structural/constitutional isomer of a compound contains the same number and type of atoms, but with a different connectivity ( i.e. , arrangement of bonds) between them. Position isomers aka posit...

An inorganic/organic compound can work as an oxidizing agent for an organic compound. Depending on the substrate, an oxidant may produce an alcohol/aldehyde/epoxide, a carboxylic acid/diol/ketone, among many others. Chemoselectivity and stereochemistry are observed as well. Question: Predict the major product(s) of the following reaction: Click/tap to enlarge the image Solution infographic: Click/tap to enlarge the image POS = Plane of symmetry Outfoxing oxidizing agent❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Ncert. Chemistry : Textbook for Class XII - Part.II ; National Council Of Educational Research And Training: New Delhi. (2)     Brown, C.; Ford, M. Higher Level Chemistry , 2nd ed.; Pearson Education: Harlow, Essex, 2014. (3)      Graham, T. W.; Fryhle, C. B.; Snyder, S. A. Organic Chemistry. ; Hoboken, Nj John Wiley Et Sons, Inc, 2016. (4)    ...

In thermodynamics the reference is the internal energy (in chemistry). The internal energy of a thermodynamic system is the energy of the system as a state function, measured as the amount of energy required to bring the system from its standard internal state to its internal state of interest. Anything that increases internal energy is positive and that decreases internal energy is negative. The first law of thermodynamics states that, when energy passes into or out of a system (as work, heat, or matter), the system's internal energy changes in accordance with the law of conservation of energy. Question: A heat engine carries 1 mol of an ideal monatomic gas around the cycle as shown in the figure below. What are the amounts of heat added in the process AB and heat removed in the process CA ? Click/tap to enlarge the image Solution: Click/tap to enlarge the image q = Heat, C v = Heat capacity at constant volume, C p = Heat capacity at constant pressure,   Δ T = Chan...

Lithium aluminum hydride , LiAlH 4 or Li[AlH 4 ] ( LAH ) is an inorganic compound that is typically a strong reducing agent. LAH is used especially for the reduction of esters, carboxylic acids, and amides. A reducing agent may or may not be selective in an organic reaction (chemoselectivity). The nature of reduction may change depending on the stoichiometric use and/or elevated temperature and/or use of another reagent like a catalyst. If the product has a new chiral center, stereoisomers may be obtained (stereochemistry). Since LAH is a hydride donor, it is dangerously reactive toward water, releasing Hydrogen gas. Wheel of LAH : Click/tap to enlarge the image Substrates -> Products (on the infographic): Esters -> 1 0  alcohols Carboxylic acids -> 1 0 alcohols Acid chlorides -> 1 0 alcohols Aldehydes -> 1 0 alcohols Ketones -> 2 0 alcohols Epoxides -> 2 0 / 3 0  alcohols Haloalkanes -> Alkanes Nitriles -> 1 0 amines Amides -> 1 0 a...

Electromotive force ( EMF ) or electromotance is an energy transfer to an electric circuit per unit of electric charge. An electrochemical cell is a device that either generates electrical energy from chemical reactions in a so-called galvanic or voltaic cell commonly known as batteries (which may have one or more than one cell connected in series), or induces chemical reactions (electrolysis) by applying external electrical energy in an electrolytic cell. Electrons flow through the external circuit through the negative electrode (anode) toward the positive electrode (cathode) during discharge when the reactions lower the chemical potential of the cell; so, discharging transfers energy from the cell to wherever the electric current dissipates its energy, mostly in the external circuit. These reactions and transports go in the opposite direction during charging (or recharging). Mnemonics: O IL R IG ( O xidation I s L oss, R eduction I s G ain) An Ox, Red Cat ( An ode Ox idation, Red ...

Tacticity is the orderliness of the succession of configurational repeating units (stereochemistry) along the main chain of a macromolecule or polymer. Tacticity can be described using pairs of adjacent stereogenic units, known as diads, and longer sequences, viz ., triads, tetrads, and pentads. Three types of triads are as follows: Click/tap to enlarge the image The substituents are placed randomly along the chain in atactic macromolecules and may occupy any specific but potentially complex sequence of positions along the chain in eutactic polymers. The tacticity of a polymer is its synthetic method dependent. International union of pure and applied chemistry ( IUPAC ) allows the term for isotactic macromolecules with at least 95% m diads (or r for syndiotactic) if that looser usage is explained. Tactics on tacticity❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: ‌(1)      Ncert. Chemistry : Textbook for Class XII...

Projection is a two-dimensional ( 2D ) representation of a three-dimensional ( 3D ) organic molecule. The Newman projection visualizes the conformation of a chemical bond from front to back, with the front atom (proximal) represented by the intersection of three lines (a dot) and the back atom (distal) as a circle and clearly illustrates the specific dihedral angle between the proximal and distal atoms. The Fischer projection is a 2D representation of a 3D organic molecule by projection. The Natta projection (wedge-dash) is a way to project 3D organic molecules with complete stereochemistry in 2D in a skeletal formula. There are more types of projections, viz. , sawhorse projection, Mills projection & Haworth projection . Each projection in stereochemistry has their own pros and cons. A molecule's R/S labeling (absolute configuration) is done using the CIP ( Cahn-Ingold-Prelog ) priority rules. The Newman projection is not quite compatible to using the C...

Electromotive force ( EMF ) or electromotance is an energy transfer to an electric circuit per unit of electric charge. An electrochemical cell is a device that either generates electrical energy from chemical reactions in a so-called galvanic or voltaic cell commonly known as batteries (which may have one or more than one cell connected in series), or induces chemical reactions (electrolysis) by applying external electrical energy in an electrolytic cell. Electrons flow through the external circuit through the negative electrode (anode) toward the positive electrode (cathode) during discharge when the reactions lower the chemical potential of the cell; so, discharging transfers energy from the cell to wherever the electric current dissipates its energy, mostly in the external circuit. These reactions and transports go in the opposite direction during charging (or recharging). Mnemonics: O IL R IG ( O xidation I s L oss, R eduction I s G ain) An Ox, Red Cat ( An ode Ox idation, Red ...

An inorganic compound can work as an oxidizing agent for an organic compound. Depending on the substrate, an oxidant may produce an alcohol/aldehyde/epoxide, a carboxylic acid/diol/ketone, among many others. Chemoselectivity and stereochemistry are observed as well. Jones reagent uses Chromium trioxide in an acetonic acidic medium. Question: A chiral alcohol is oxidized by Jones reagent to an achiral ketone. Which of the following isomers meets this fact? Click/tap to enlarge the image Solution infographic: Click/tap to enlarge the image Outwitting oxidizing agent❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Ncert. Chemistry : Textbook for Class XII - Part.II ; National Council Of Educational Research And Training: New Delhi. (2)      Graham, T. W.; Fryhle, C. B.; Snyder, S. A. Organic Chemistry. ; Hoboken, Nj John Wiley Et Sons, Inc, 2016. (3)      Reusch, W. Virt...

Enantiomers ( aka optical isomer, antipode, or optical antipode) are non-superimposable mirror images of a pair of molecular entities. For the Mills projection formula, a 180º rotation in the plane of the paper (or screen) does not convert the structure to the other enantiomer, but flipping the structure over (a 180º rotation out of the plane) does. Question: Which two formulas represent a pair of enantiomers? Click/tap to enlarge the image Solution infographic: Click/tap to enlarge the image Mesmerizing Mills projections❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Ncert. Chemistry : Textbook for Class XI - Part.II ; National Council Of Educational Research And Training: New Delhi. (2)      Graham, T. W.; Fryhle, C. B.; Snyder, S. A. Organic Chemistry. ; Hoboken, Nj John Wiley Et Sons, Inc, 2016. (3)      Brown, C.; Ford, M. Higher Level Chemistry , 2nd ed.; Pearson Educat...

Chemical equilibrium is the state in which both the reactants and products in a chemical reaction are present in concentrations that have no more propensity to change with time, s.t. there is no visible alteration in the system properties. This state results when the forward reaction proceeds at the same rate as the reverse/backward reaction, and is known as dynamic equilibrium. The equilibrium constant of a chemical reaction is the value of its reaction quotient at chemical equilibrium. For a given set of reaction conditions like temperature, solvent, and ionic strength, the equilibrium constant is independent of the initial concentrations of the reactants and products. The equilibrium constant will be dimensionless only if the number of moles of the reactants is equal to that of the products. Dalton’s law ( aka Dalton’s law of partial pressures) states that the total pressure exerted is equal to the sum of the partial pressures of the individual gases in a mixture of non-reacting...