Q: Why is o- hydroxy benzaldehyde a liquid whereas p-hydroxy benzaldehyde a solid , with high MP, at room temperature ? A: o- hydroxy benzaldehyde
Tag: chemical bonding
102.CHEMICAL BONDING (49)- Secondary bonding(6)- Hydrogen Bonding (4)
We continue to study the physical manifestations of H- bonds and their importance. Protein folding Hydrogen bonds are an integral part of the protein structure.
101.CHEMICAL BONDING (48)- Secondary bonding(5)- Hydrogen Bonding (3)
We studied hydrogen bonding in the last two posts. In this post, we will study the types of this bonds and their implications . The H-bond
100.CHEMICAL BONDING (47)- Secondary bonding(4)- Hydrogen Bonding (2)
I take immense pride in writing the 100th post on this blog. I am glad that I could continue writing throughout my pregnancy, after my daughter was
99.CHEMICAL BONDING (46)- Secondary bonding(3)- Hydrogen Bonding (1)
In this post we start discussing a type of secondary bonding, without which life would not be possible !! How is hydrogen bonding and life
98.CHEMICAL BONDING (45)- Secondary bonding(2)- Induced dipole- Induced dipole interactions.
S2.Induced dipole– Induced dipole interactions. Vander Waals bond , London dispersion force and induced dipole – induced dipole interactions all mean the same. This type of
97.CHEMICAL BONDING (44)- Secondary bonding(1)- Dipole dipole interactions.
We have already seen in post # 54 that the main difference between primary and secondary bonding is that in secondary bonding THERE IS NO
96.CHEMICAL BONDING (43)- Metallic bonding(2).
As we discussed in the last post , the free electron gas model is not infallible. Almost 30 years after the electron gas model was
95.CHEMICAL BONDING (42)- Metallic bonding(1).
P3.THE METALLIC BOND. In this post we shall discuss the last kind of primary bond – The metallic bond. We see many objects in our everyday
94.CHEMICAL BONDING (41)- Co ordinate covalent bond.
This post is dedicated to studying the co-ordinate covalent. This is a bond formed between an electron rich and an electron poor species. Electron rich
93.CHEMICAL BONDING (40)- Covalent Bonding(39) – Molecular Orbital Theory(12)- Heteronuclear diatomic molecules(3).
CO in high concentration is fatal in less than 5 mins !! The worst part is that this is an odorless and colorless gas and
92.CHEMICAL BONDING (39)- Covalent Bonding(38) – Molecular Orbital Theory(13)- Heteronuclear diatomic molecules(2)- HF.
From this post onwards, we shall study some examples and learn how bonds are formed between two different atoms. Hydrogen fluoride (HF) – We
91.CHEMICAL BONDING (38)- Covalent Bonding(37) – Molecular Orbital Theory(12) – Heteronuclear Diatomic molecules(1)
With this post we start discussing MOT theory for diatomic heteronuclear molecules – molecules formed by two different atoms. The MO diagrams for heteronuclear atoms
90. CHEMICAL BONDING (37)- Covalent Bonding(36) – Molecular Orbital Theory(11) – Fluorine.
Fluorine molecule (F2) – F (9) 1s2 2s2 2p5 Two fluorine atoms bring 7 electrons each to the table and thus the 10 electrons get arranged
89. CHEMICAL BONDING (36)- Covalent Bonding(35) – Molecular Orbital Theory(10)- Nitrogen molecule.
Nitrogen molecule (N3) – N (7) 1s2 2s2 2p3 When we construct the MO diagram for nitrogen , we will only draw the valence 2s and
88.CHEMICAL BONDING (35)- Covalent Bonding(34) – Molecular Orbital Theory(9)- Helium ,sp mixing.
Helium molecule (He2) – He (2) – 1s2. Helium has two electrons in the 1s orbital. Thus, when we draw the MO diagram, two electrons
87. CHEMICAL BONDING (34)- Covalent Bonding(33) – Molecular Orbital Theory(8) – Overlaps and symmetry(2)
Pi Symmetry Orbitals with pi symmetry are NOT symmetric w.r.t to the internuclear axis. When rotated around the axis, they produce a phase change (which
86.CHEMICAL BONDING (33)- Covalent Bonding(32) – Molecular Orbital Theory(7) – Overlaps and symmetry(1)
Overlaps & Symmetry Based on how the bonds are formed, the interaction between two AOs can have following symmetry- i) Sigma (σ) ii) Pi (π
85.CHEMICAL BONDING (32)- Covalent Bonding(31) – Molecular Orbital Theory(6)- Symmetry of MOs.
SYMMETRY OF MOLECULAR ORBITALS. Based on symmetry ,the orbitals can be classified as – GERADE MOs and UNGERADE MOs. Gerade MOs ⇒ Gerade = Even
84. CHEMICAL BONDING (31)- Covalent Bonding(30) – Molecular Orbital Theory(5).
In this post we shall begin by constructing MO diagrams. We shall begin with the simplest of all homonuclear diatomic molecules – The H2 molecule.
83.CHEMICAL BONDING (30)- Covalent Bonding(29) – Molecular Orbital Theory(4)- LCAO approximation(2).
We have seen in the periodic table series , that the electronic configuration tells us where exactly the electron is. Configuration means order… so
82.CHEMICAL BONDING (29)- Covalent Bonding(28) – Molecular Orbital Theory(3)- LCAO approximation(1).
LINEAR COMBINATION OF ATOMIC ORBITALS (LCAO approximation) MOT is incorporated in quantum mechanics. As we have already discussed that classical physics (physics
80.CHEMICAL BONDING (27)- Covalent Bonding(26) – Molecular Orbital Theory(1).
Molecular orbital theory(MOT) is a quantum mechanical approach to bonding.Thus, this theory considers an orbital as a wave function(ψ).In order to understand MOT , it
79.CHEMICAL BONDING (26)- Covalent Bonding(25) – Problems(2).
Q: Which of the following statements for bond angles (θ) in CH4 and CH2F2 molecules is true – A] θ CH4 > θ CH2F2 B] θ CH4 < θ CH2F2 C] θ
78.CHEMICAL BONDING (25)- Covalent Bonding(24) – Problems(1).
Q: Why does PCl5 exists but NCl5 does not? A. Ionization energy of N is very high B.N does not have vacant d- orbitals C.It does not
75.CHEMICAL BONDING (22)- Covalent Bonding(21)- Hybridization in solid state
How compounds exist in solid state ? Compounds exist as ions in solid state. Consider the following example – PCl5 molecule – This molecule has
74.CHEMICAL BONDING (21)- Covalent Bonding(20)- Bent’s rule(3).
Example 3 – PCl3F2 molecule . This molecule has TBP geometry with two F atoms and three Cl atoms as substituents.According to Bent’s rule –
73.CHEMICAL BONDING (20)- Covalent Bonding(19)- Bent’s rule(2).
After having learnt the statement of Bent’s rule in the earlier post , let us now study the rule with some examples. We know that bond angle(θ) ∝
72.CHEMICAL BONDING (19)- Covalent Bonding(18)- Bent’s rule(1).
In this post we are going to learn a comparatively new rule, proposed by Henry Bent.Henry Bent (1926-2015) was an American physical chemist who
71.CHEMICAL BONDING (18)- Covalent Bonding(17)- The Bond Angle.
We have already studied that the angle between the central and terminal atoms of a molecule is called as a bond angle.In this post we
