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Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Ashutosh singh
24 - A 25 - A Examples of network solids include diamond with a continuous network of carbon atoms and silicon dioxide or quartz with a continuous three-dimensional network of SiO2 units.
Compounds that contain fewer valence electrons than valence orbitals are referred to as electron deficient. For example, diborane has 10 valence orbitals (four from each boron atom and one from each hydrogen) but 12 valence electrons. In order to engage all of their valence orbitals in bonding, the atoms in electron deficient compounds sometimes form three-center two-electron (3c-2e) bonds. Remember that a pair of electrons is required to make a single covalent bond. In a 3c-2e bond, the two electrons are shared by three atoms with each atom contributing one orbital to the formation of the bond.
Shib, here's the full concept - We can conceptualize the formation of the hydrogen bridge bonds by imagining two sp3 hybridized BH2 fragments coming together with two H atoms. Each boron atom would use two of its sp3 hybrid orbitals and two electrons to form the terminal B - H bonds. Each boron atom has one electron and two sp3 orbitals remaining as shown in the diagram to the left. The 1s orbital of a hydrogen atom can overlap with an occupied sp3 orbital from one boron atom and an unoccupied sp3 hybrid from the other boron atom. The result is the formation of a three-center two-electron hydrogen bridge bond. The other bridge bond is formed similarly.
sir for question no 24 a,b,c r correct
Yes Shib. A, B, C all will be correct. I thought it's single correct type so as soon as I saw B2H6, I jumped onto it! Yes, they are all correct.
But, the whole concept which I explained above is totally correct and you must write them down somewhere on your notes, it'll help you. 😊
Dear Shib, please accept the answer! 🙏😊