MyChemistryHomework

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...