Project IIT- Hydrogen spectrum Wavelengths -PhysiChemistry

Regarding hydrogen spectrum- Don’t forget to remember first and last lines of Lyman, Balmer series and Paschen series.   For Balmer series, remember second, third and fourth line as well. Last line wavelength is also called series limit. It can be calculated by taking n2 as infinity. Last line wavelength is the shortest wavelength and hence […]

Bredt’s rule and Decarboxylation (Of beta-carboxylic acids)

Unless rings are large enough (Bredt’s Rule), At small bicyclic bridgehead positions, planarity is difficult to attain, in other words, bridgehead carbon cannot have a pure “p” orbital. Hence, Bridgehead free radicals are pyramidal. Bridgehead carbocations are not possible. At bridgehead carbons, the double bond is not possible. Unlike I, II (being a bridgehead olefin) […]

Shielding effect and Effective nuclear charge

CALCULATION OF Zeff: Slater’s Rules 1) Write the electron configuration for the atom using the following design ( Write the electronic structure of the atom in groupings as follows): (1s), (2s, 2p), (3s, 3p), (3d), (4s, 4p), (4d), (4f), (5s, 5p), (5d), (5f)… 2) Any electrons of principal quantum number higher than the “electron of […]

All about Back Bonding

In Classical sense, Back bonding can be best described As: “dative π-bonding” btw orbitals (any two p or d orbitals or a mixture of both) of appropriate energies (& obviously parallel). [Here, by Appropriate energies, we mean to infer that Orbitals involved are of proper symmetry, shape & size] Back-bonding can also be visualised as […]

Understanding the Myriad of Inorganic chemistry

Did you know: What is Bond order of CO+?  Well, it’s 3.5 F2 is best oxidising agent? Well, it’s wrong. Check p-273, Q8.16 NCERT XI Chemistry. Perxenate ion, (XeO6)4– is Stronger oxidising agent than F2. Solid PCl5, solid PBr5, solid GaCl2, solid XeF6, solid N2O5, solid N2O4, solid N2O3 , solid Cl2O6, solid I2Cl6, are […]

pH of Amphiprotic species & Isoelectric pH

NaHCO3 is amphiprotic species just like NaHSO4, NaHS, Na2HPO4, NaH2PO4. etc. In such cases the solution pH is dependent on the two ionization constants of the amphiprotic substance and independent of the concentration of the amphiprotic substance in the solution. However, they do not hold pH well and are not effective as buffer solutions. Here […]