Welcome to Chem Zipper.com......: CHEMICAL BONDING:

Search This Blog

Showing posts with label CHEMICAL BONDING:. Show all posts
Showing posts with label CHEMICAL BONDING:. Show all posts

Sunday, September 26, 2021

What is the misconceptions about resonance?

Many misconceptions are associated with resonance and the same need to be dispelled. 
You should remember that : 
(1) The cannonical forms have no real        existence.
(2)The molecule does not exist for a       certain fraction of time in one     cannonical form and for other       fractions of time in other cannonical       forms.
(3) There is no such  equilibrium between the cannonical forms as we have between tautomeric forms (keto and enol) in tautornerisrn. 
(4) The molecule as such has a single       structure which is the resonance       hybrid of the cannonical forms and       which cannot as such be depicted by     a single Lewis structure.
(5) Resonance is a theoratical concept. The resonating structure have no physical reality, i.e., they do not actually exist. Only the hybrid structure exists. The hybride structure can not be represented on the paper but resonating structure can be represented.

Among I2, ICI, CCl4, PCl3, POCl3, which molecules exhibit dipole moment?

I2 and CCl4 are symmetrical molecule, their dipole moment is zero, while ICl, PCl3 And POCl3    will exhibit dipole moment.


Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

Among CH3OH, CH4, CF4, CO2 and CH3F, which has the highest dipole moment?

CH4, CF4 (both tetrahedral), and CO2 (linear) are symmetrical molecules. Their dipole moment is zero. Since fluorine is more electronegative than oxygen, the dipole moment of CH3F is higher that of CH3OH. Thus, among CH3OH, CH4 CO2 and CH3F, CH3F has the largest dipole moment.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

Thursday, August 5, 2021

How many molecules form coordinate bonds in CuSO4.5H2O?

In Cupper Sulphate pentahydrate (CuSO4.5H2O) Cu is coordinated with 4 water molecules and two more oxygen atoms from Sulphate ion. And hence the coordination number of Cu (II) ion is six and hybridization is sp3d2 with distorted octahedral geometry. Now fifth water molecule is hydrogen bonded and is deeply embedded in crystal.

Thus it is clear that four (4) water molecules are coordinated and one (fifth one) water molecule is bonded with hydrogen bond. And its formula also written as [Cu(H2O )4SO4].H2O

Releted Questions:

(1) What is the structure of Blue vitriol (CuSO4) .5H2O also represent the H-Bond with water molecules?

(2) Why bond angle of hydrides of group 15, decreases down the group?

(3) Why SF6 behave inert towards hydrolysis?

(4) What are the SESQUI OXIDES ? give the examples.

(5) Arrange in increasing order of extent of hydrolysis [ CCI4, MgCI2, AICI3, PCl5, SiCI4].

(6) Why SF6 behave inert towards hydrolysis?

(7) Although Sulphur contain vacant d-orbital but SF6 does not under go hydrolysis. Why ?

(8) Phosphorus can form PCl5 but nitrogen can not form NCl5 why?

(9) Why PCl3 hydrolysed while NCl3 can not be hydrolysed?

(10) CCl4 can not be hydrolysed but SiCl4 can be. Why?

(11) Silianol (SiH3OH) is more acidic than methanol (CH3OH) why?

(12) How many hydrogen bonded water molecules does CuSO4.5H2O have?

How many hydrogen bonded water molecules does CuSO4.5H2O have?

In Cupper Sulphate pentahydrate (CuSO4.5H2O) Cu is coordinated with 4 water molecules and two more oxygen atoms from Sulphate ion. And hence the coordination number of Cu (II) ion is six and hybridization is sp3d2 with distorted octahedral geometry. Now fifth water molecule is hydrogen bonded and is deeply embedded in crystal.

Thus it is clear that four (4) water molecules are coordinated and one (fifth one) water molecule is bonded with hydrogen bond. And its formula also written as [Cu(H2O )4SO4].H2O

Releted Questions:

Wednesday, July 28, 2021

What is the difference of dipole moment of NH3 and NF3 respectively?

 Both NH3 and NF3 have sp3 hybridization and trigonal pyramidal shape.


Fluorine has more electronegative than nitrogen but NH3 has more dipole moment than NF3.  In NH3, Nitrogen is more electronegative than Hydrogen. So Nitrogen pulls the electrons from Hydrogen towards itself and so, the direction of moment due to the N-H bonds is in the same direction as that of the lone pair of electrons on Nitrogen. Hence here additive effect appears while in case of NF3, Fluorine is more electronegative than Nitrogen. So fluorine pulls electrons from nitrogen towards itself  so that direction of moment due to N-F bonds is in the opposite direction as the lone pair of electron on nitrogen atom. Hence it is clear dipole moment of NH3 is more than NF3.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

Why dipole moment of NH3 is lower than NH3?

Both NH3 and NF3 have sp3 hybridization and trigonal pyramidal shape.

Fluorine has more electronegative than nitrogen but NH3 has more dipole moment than NF3.  In NH3, Nitrogen is more electronegative than Hydrogen. So Nitrogen pulls the electrons from Hydrogen towards itself and so, the direction of moment due to the N-H bonds is in the same direction as that of the lone pair of electrons on Nitrogen. Hence here additive effect appears while in case of NF3, Fluorine is more electronegative than Nitrogen. So fluorine pulls electrons from nitrogen towards itself  so that direction of moment due to N-F bonds is in the opposite direction as the lone pair of electron on nitrogen atom. Hence it is clear dipole moment of NH3 is more than NF3.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

Which NH3 and NF3 have the highest dipole moment and why?

Both 

Fluorine has more electronegative than nitrogen but NH3 has more dipole moment than NF3.  In NH3, Nitrogen is more electronegative than Hydrogen. So Nitrogen pulls the electrons from Hydrogen towards itself and so, the direction of moment due to the N-H bonds is in the same direction as that of the lone pair of electrons on Nitrogen. Hence here additive effect appears while in case of NF3, Fluorine is more electronegative than Nitrogen. So fluorine pulls electrons from nitrogen towards itself  so that direction of moment due to N-F bonds is in the opposite direction as the lone pair of electron on nitrogen atom. Hence it is clear dipole moment of NH3 is more than NF3.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

Which has more dipole moment of NH3 or NF3?

Both 

Fluorine has more electronegative than nitrogen but NH3 has more dipole moment than NF3.  In NH3, Nitrogen is more electronegative than Hydrogen. So Nitrogen pulls the electrons from Hydrogen towards itself and so, the direction of moment due to the N-H bonds is in the same direction as that of the lone pair of electrons on Nitrogen. Hence here additive effect appears while in case of NF3, Fluorine is more electronegative than Nitrogen. So fluorine pulls electrons from nitrogen towards itself  so that direction of moment due to N-F bonds is in the opposite direction as the lone pair of electron on nitrogen atom. Hence it is clear dipole moment of NH3 is more than NF3.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.


Compare the dipole moment of H2O and F2O.

Let’s draw the structure of both two compounds and then analyses it.

In both H2O and F2O the structure is quite the same. In H2O as O is more electronegative than hydrogen so the resultant bond dipole is towards O, which means both the lone pair and bond pair dipole are acting in the same direction and dipole moment of H2O is high. In case of F2O the bond dipole is acting towards fluorine, so in F2O the lone pair and bond pair dipole are acting in opposition resulting in a low dipole.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

Dipole moment of CCl4 is zero while that of CHCl3 is non zero. explain.

Both CCl4 & CHCl3 have tetrahedral structure but CCl4 is symmetrical while CHCl3 is non-symmetrical.

Due to the symmetric.al structure of CCl4 the resultant of bond dipoles comes out to be zero. But in case of CHCl3 it is not possible as the presence of hydrogen introduces some dissymmetry.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

 

CO2 has got dipole moment of zero why?

The structure of CO2is this is a highly symmetrical structure with a plane of symmetry passing through the carbon. The bond dipole of C–O is directed towards oxygen as it is the negative end. Here two equal dipoles acting in opposite direction cancel each other and therefore the dipole moment is zero.


The Dipole moment of chloromethane is more than fluoromethane. Explain.

Since C-Cl bond is longer than C-F bond, thus it is compensates the lower electronegativity factor of chlorine. Hence dipole moment of chloromethane is more than fluoromethane.