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Most recommended books of organic chemistry for IIT JEE mains and advanced exams-part-2


(7) Workbook for Organic Synthesis

Book by Stuart Warren
(8) Advanced Organic Chemistry: Reaction Mechanisms
Book by Reinhard Bruckner
(9) Organic Synthesis: The Disconnection Approach 

Workbook By Stuart Warren
(10) Cengage Organic Chemistry


Book by K.S. Verma
(11) Organic Chemistry
This is one of most famous book of chemistry it is not only a book, this is more over like your  best friend. The book explains each and every concept precisely and accurately, this is a holy book for IIT, CSIR and other competitive exams.

I have no words to do review on that book but I want to say without learning that book chemistry syllabus of any exams cannot be complete so must buy it and learn organic like a story book.

Anyone can by this awesome book from Amazon followed by this link Clayden Organic Chemistry on Amazon



Most recommended books of organic chemistry for IIT JEE mains and advanced exams-part-1

                 
                                   
(1) Organic Chemistry
Book by Paula Yurkanis Bruice



(3) Organic Chemistry
Book by Jagdamba Singh

(4) March’s Advanced Organic
Book by Jerry March

(5) Morrison and Boyed Organic Chemistry
Boook by Morrison Boyed

What are the increasing order of molar conductivity of first group elements in water ?

Li+ < Na+ < K+ < Rb+ < Cs+
Li+ ion being heavily hydrated due to smallest size and hence it's hydrated radius become very large as result has the lowest mobility and Cs+ ion being less hydrated and smallest ionic radius hence has the highest mobility.

What are the increasing order of ioni radii of first group elements in water ?

Cs+ < Rb+ < K+ < Na+ < Li+
The ions in solution are present as hydrated ions. The smaller the size of the ion, the greater the extent of hydration. So the size of hydrated ions becomes larger for smaller sized ion and vice versa. 

Though enol form is less stable than keto form, phenol exists in enol form, why?

Enol form is much more stable than keto form because of great stability associated with aromatic ring which is absent in keto form.



What are the difference between Tautomerism & Resonance ?


(1) In tautomerism, an atom changes place but resonance involves a change of position of pi-electrons or unshared electrons.
(2) Tautomers are different compounds and they can be separated by suitable methods but resonating structures cannot be separated as they are imaginary structures of the same compound.
(3) Two tautomers have different functional groups but there is same functional group in all canonical structures of a resonance hybrid.
(4) Two tautomers are in dynamic equilibrium but in resonance only one compound exists.
(5) Resonance in a molecule lowers the energy and thus stabilises a compound and decreases its reactivity. But no such effects occur in tautomerism.
(6) In resonance, bond length of single bond decreases and that of double bond increases e.g. all six C—C bonds in benzene are equal and length is in between the length of a single and a double bond.
(7) Resonance occurs in planar molecule but atoms of tautomers may remain in different planes as well.
(8) Tautomers are indicated by double arrow in between the two isomers but double headed single arrow is put between the canonical (resonating) structures of a resonating molecule.

4- nitrophenol is more acidic than 3,5 - dimethyl –4-nitro-phenol. Explain.

It is explained in terms of inductive effect and hyperconjugation.

Explain why aniline is less basic than ammonia?

The lone pair present at the nitrogen in aniline is delocalized in the ring (by 
resonance) and hence, it is not free for protonation, while in ammonia. It is 
present at nitrogen all the time, hence it is readily available for ptrotonation.

Why benzyl carbonium ion is more stable than ethyl carbonium ion?

Due to resonance benzyl carbonation is more stable than ethyl carbonation.

Among orthochlorophenol and orthofluorophenol, which will be a stronger acid and why?


The one having a weaker conjugate base will be a stronger acid. If the conjugate 
base has to be weak, the negative charge has to be delocalised to a larger 
extent.
In o-chlorophenol
Due to the availability of vacant orbitals in chlorine, the negative charge is delocalised to a larger extent. The same cannot take place in case of F as F does not have vacant orbitals. So, o-chlorophenol, having a weaker conjugate base, becomes a stronger acid.

Related Questions
(1)Benzylamine is a stronger base than aniline. Explain.
(2) Why is always the resonance effect dominating over the inductive effect?
(3) Why benzyl carbonium ion is more stable than ethyl carbonium ion.?

Alcohols and Phenols both are acidic but phenols are more acidic. Why?

AIcohols and phenols. borh are acidic in nature because they Iiberate H+ with active metals. But alcohols are weaker acids than phenols because,  
(1)  alcohols fails to turn blue litmus red while phenol do so.
(2) alcohols fails to neutralize alkalies whereas phenols do so:
(3) Both phenol and phenoxide ions exhibit resonance, whereas alcohols and alkoxide ion do not.
(4) Due to resonance, positive charge 's developed over "O"of phenol, this weakens O-H bond and facilitates release of a proton. On the other hand. due to electron donating nature of alkyl group. -O-H bond is strengthened. therefore. it hinders the release of proton.      
(5) The phenoxide ion is more stable than phenol, due to o greater dispersal of  negative charge, therefore. equilibrium get shifted to forward direction. whereas alkoxide ion is less stable than alcohols due to intensification of negative charge, so equilibrium get shifted towards backward direcrion. 
Due to these fact it is clear that phenols are more acidic than alcohols. 



Best book of Organic Chemistry for IIT Advanced, CSIR/NET/ GATE and other compatative exams !

This is one of most famous book of chemistry it is not only a book, this is more over like your  best friend. The book explains each and every concept precisely and accurately, this is a holy book for IIT, CSIR and other competitive exams.
I have no words to do review on that book but I want to say without learning that book chemistry syllabus of any exams cannot be complete so must buy it and learn organic like a story book.

Anyone can by this awesome book from Amazon followed by this link Clayden Organic Chemistry on Amazon

Imortant reasoning Questions of Boron family (13th group) for IIT mains/advanced and NEET also !

Why Ga has small size than Al exceptionally

Why aqueous solution of borax reacts with two moles of acids ?

What is structure of solid Ortho Boric acid ?

What is the structure of trimetaboric acid and trimetaborate ion?  

Why Borazine is more reactive than benzene towards Electrophic Aromatic substitution reactions ?

Why Borazine (B3N3H6) is also known as inorganic benzene ?.

Why B-F bond length in BF3 is shorter (130 pm) than B-F bond Iength in BF4- (143 pm)?. Explain.

Why B-F do not exist as dimer?. Explain.

Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?

Why Boric acid become strong acid in the presence of cis 1,2-diol or 1,3-diol ?

Four-center two-electron bond (4C-2e Bond): Structure of AlCl3:

What is the molecular formula of Borax ?

What is the difference between the structure of AlCl3 and diborane?

Titration of Borax: Tincal : Suhaga :

Structure of Borax: Tincal or Suhaga:

Titration of Boric Acid:

DIBORANE-HYDRIDE OF BORONE-(B2H6):

CHEMICAL PROPERTIES OF DIBORANE:

STRUCTURE OF BORON NITRIDE:

STRUCTURE OF BORAZINE OR BORAZOLE:

STRUCTURE OF DIBORANE :

BORIC ACID (H3BO3) :

BORAX BEAD TEST:

 

 

Related Questions:

 

What are Silicones? explain with examples.

 

 

 

 

 

What happened when lead oxide is strongly heated ?

When heated, lead(II) nitrate crystals decompose into lead(2)oxide, oxygen and nitrogen dioxide.

2 Pb(NO3)2(s) → 2 PbO (s) + 4 NO2(g) +O2(g)

Due to this property, lead nitrate is used in firewoks.

Iodine forms I3- but F2 does not form F3- ions. Why?

I2 because of the presence of vacant d– orbitals accepts electrons form 
I ions to form I3 ions but F2 because of the absence of d – orbitals does not 
accept electrons from F ions to form F3- ions.

Why the elements of the second row (first short period) show a number of differences in properties from other members of their respective families?

The differences in the properties of the first member of a group from those of the other members are due to 
(i) the smaller size of atom. 
(ii) presence of one inner shell of two electrons and 
(iii) absence of d – orbitals.

Why is nitrous oxide (N2O) used as an anaesthetic in dentistry?

N2O is used as an anaesthetic in dentistry because of its inertness.

Where is liquid nitrogen used for?

Liquid nitrogen is used as a refrigerant to preserve biological specimen, and also used for providing low temperature in super conductivity.

Why does H3PO3 acts as a reducing agent but H3PO4 does not?

H3PO3 contains one P H bond and hence acts as a reducing agent but H3PO4 does.

Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.














Which of the following is/are not known? PCl3, AsCl3, SbCl3, NCl5, BiCl5

(1) NCl5 (due to absence of d-orbitals)
(2) BiCl5 (Bi5+ being an oxidizing agent oxidizes Cl ion to Cl2 and Cl-ion being a reducing agent reduces Bi5+ to Bi3+).

Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.














Why bismuth has low m.p. while if going down the group m.p. increases?


This may presumably be due to more tendency of Bi to form three rather than five covalent bonds (inert pair effect). Thus there are weak forces of attraction between their atoms in solid state, accounting for its low m.p.

Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.
















Which element among group 15 elements has lowest boiling point?

Nitrogen (N2) 

Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.

















Why white phosphorous is stored under water?

White phosphorous is very reactive and will spontaneously inflame in air so it is stored under water.
Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.
















Which allotrope of phosphorous is used on top head of match stick?

Red Phosphorous is used on top head of match stick.

Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.














Why the first ionization energy of group 15 elements much higher than those of corresponding group 14 elements?

The first ionization energy of group 15 elements much higher than those of corresponding group 14 elements this is due to increase in nuclear charge and extra stable configuration of the elements of this group. The extra stability of configuration is attributed to the exactly half filled p – orbitals in their valence shells.
Related Questions:



Trisilyl amine, N(SiH3)3 is planar whereas trimethyl amines N(CH3)3 is pyramidal. Explain why?.















Metallurgy- Extraction of elements, and purification methods:

METALLURGY-INTRODUCTION:
PYROMETALLURGY:

How to determine Basic order of different amines and it derivatives ?

  1. How is base strength related to the availabihty of the electron-pair?
  2. Amines are more basic than ammonia why?
  3. What is relative basic strength order 1° amines , 2°amines and 3° amines ? Explain:
  4. Give an explanation for the fact that Guanidine NH=C(CH3)2 is a stronger base than most of amines?
  5. Arrange in correct order of basic Character of aniline, pyrrol, pyridine and piperidine?
  6. What is correct basicity order of pyridine, pyridazine, pyrimidine and pyrazine ?
  7. Give an explanation for the fact that Guanidine NH=C(CH3)2 is a stronger base than most of amines?
  8. Arrange in correct order of basic Character of aniline, pyrrol, pyridine and piperidine?
  9. What is correct basicity order of pyridine, pyridazine, pyrimidine and pyrazine ?
  10. Why pyridine is more basic than Pyrrole?
  11. Why pyrimidine is less basic than pyridine?
  12. Imidazole is more basic than pyridine? Why?
  13. Biological Important of Imidazole and structure:
  14. Pyridine is almost 1 million times less basic than piperidine? Why?
  15. Cyclohexylamine amine is the stronger base than Aniline? Why?
  16. Tetrahydroquinoline amine is the stronger base than Tetrahydroisoquinoline? Why?
  17. Arrange the following in the order of increasing basicity : p-Toluidine, N, N-Dimethyl-p-toluidine, p-Nitroaniline, Aniline. (I.I.T.1986)
  18. Arrange the following in the increasing order of their acid strength : Methyl amine, Dimethyl amine, Aniline, N-methyl aniline (I.I.T, 1988).







What are Zeeman and Stark effects? Were they explained by the Bohr’s theory?

The splitting of spectral lines into many components in the presence of a magnetic field is called Zeeman effect.

Analogously, the splitting of spectral lines into many components in the presence of an electric field is called Stark effect. 
These effects could not be explained within the framework of Bohr's theory and required the presence of multiple non-circular orbits corresponding to each energy level. An effort, with some degree of success, was made by Sommerfeld to explain these phenomena by invoking multiple elliptical orbits corresponding to each energy level. The Bohr Sommerfeld theory was ultimately discarded along with Bohr's model for other reasons.

Ionization energy of Boron is smaller than Beryllium even though effective nuclear charge is higher?

The electronic configurations of Boron and Beryllium are (B [He]1S2,2S2,2p1) and (Be [He]1S2,2S2). In Boron the outermost electron is present in the 2p orbital and is less strongly bound than the electron present in a 2S orbital of Beryllium, which will has a higher Zeff. It is easier to ionize the Boron atom.
 

The complex formation Tendency of NH3 is wisher than PH3.


SOLUTION: In NH3 lane pair is present in one of the sp3 Hybridized orbital. While in PH3 lone pair is present in pure S orbital and hence lane pair donation capacity of NH3 is stronger than PH3

What happens if two deactivating and one activating group is present on a benzene ring?

We know that reactivity of benzene ring towards electrophilic reaction depends upon presence of group on benzene ring. Benzene gives electrophilic substitution reaction due to negative pi cloud formation , if there is EWG (electron withdrawing) group on benzene ring it's negativeness decreases and reactivity also decreases and due to resonance upcoming group goes at meta position only while in the presence of ERG (electron releasing groups) it's negative ness increases and reactivity increase and due to resonance upcoming group goes at ortho and para position .
If both EWG and ERG present on benzene ring then upcoming electrophile goes to ortho and para position  according to ERG group .

What is bromoform reaction?

Haloform reaction includes Chloroform, Bromoform and Iodoform reaction, It is feature reaction of terminal methyl ketones and alpha hydroxy ketones . In which methyl ketones oxidised in the presence of I2 and NaOH ( NaOI) into Sodium salt of carboxylic acid and corresponding haloform ( Chloroform , Bromoform and Iodoform)

Is Methanal an aldehyde?

Yes ! Methanal is a aldehyde containing -CHO group. And is molecular formula is HCHO . It is more commonly known as formaldehyde. It is also first member of aldehyde homologous series.

Which is a better nucleophile, among halides ions ( fluoride, Chloride, bromide and iodide)? and Why?

Nucleophilicity of an nucleophilic depends upon nature of solvent, for example:
(1) I⁻ is a better nucleophile than F⁻ in polar protic solvents.

(2) F⁻ is a better nucleophile than Br⁻ in polar aprotic solvents.

We know that a protic solvent has an H atom bound to more electronegative elements like F, O or N. It can use its H atom to formed H-bonding with a nucleophile. Which accumulate around nucleophilic and creates a shell around the nucleophile. So that it becomes more difficult to attack the positive carbon bearing the leaving group.

F⁻ is a small ion with a high charge density. It is tightly solvated.

I⁻ is a large ion with a low charge density. It is loosely solvated. There are only a few solvent molecules to push out of the way.

Hence over all order of nucleophilicity in polar protic solvents is given as :

        [ I⁻ > Br⁻ > Cl⁻ > F⁻ ]

We know that a polar aprotic solvent does not have a hydrogen atom that can formed hydrogen bond.

But in all of them, the negative ends of the dipoles directedaway from the molecule. So that It is easy for them to solvate cations.

The positive ends of the dipoles are closer to the middle of the molecule. It is difficult for them to get close to the anions.

As the result the nucleophile has few molecules in its solvent shell. The nucleophile can more easily attack on positive carbon (electrophilic center).

Hence F⁻ becomes a much better nucleophile than chloride, 

Hence over all order of nucleophilicity in polar aprotic solvents is just reverse of that given in polar protic solvent :

        [ F⁻ > Cl⁻ > Br⁻ > I⁻ ]


Vapour density of mixture of NO2 and N24O4 is 34.4 , then percentage abundance (by volume) of NO2 in mixture is .

Molecular weight = 2×VD
                                = 2× 34.5 = 69 u
Consider ℅ of NO2 is "x" then % of N2O4 is "100-x"

What are the structure of CO2 , NO2+ , OCN- , SCN- ?

These molecules are isoelectronic so structure are also similar :

Why does CO form a coordinate bond?


In carbon monoxide molecule carbon and oxygen form a double bond by sharing of two bond pairs , in which 
carbon as well oxygen contributes 2 electrons to each other to form a double bond . 
Now octet of oxygen is completed but carbon is left with two (2) valence electrons and it has a total of six electrons so it's octet is incompleted.

Hence carbon is relatively unstable than oxygen atom because oxygen has nearest noble gas configuration of 8 electrons in their valence shell.

So in order to attain stability oxygen contributes one of its lone pair of electrons to the carbon atom in the formation of a coordinate bond . This leads to completion of octet of both carbon and oxygen .
Important note: 
In coordinate bond a pair of electrons is shared between two atoms but it is contributed by a single atom( Here contributor of lone pair is oxygen atom).

Similar Questions:

How can draw the Lewis Structure of CO?

The electronic configuration of carbon and oxygen atoms as

C6 =1s2 2s2 2p2
O8 =1s2 2s2 2p4

This information can be used to determine the Lewis Dot Structure of  Carbon monoxide (CO):

Step 1: calculate total valence electrons  for carbon and oxygen atoms.

C = 4
O = 6

Total electrons in CO molecule =10

Step 2: Find octet electrons for each atom , carbon and oxygen

C: 8
O: 8

Total octet electrons =16

Step 3: Find the bonding electrons Subtract total valence electron from total octet electrons

16-10=6 electron (3 bond pair)

Step 4: Find number of bonds between carbon and oxygen atoms  by dividing the number of bonding electrons by 2

6-electrons/2 = 3 bonds

Step 5: The rest are non bonding pairs. Subtract bonding electrons  from valence electrons .

10-6= 4e-= 2 lone pairs


The Lewis structure of CO is identical with that for HC:::CH  except that the C-H bond pair replace by lone pairs.

      "CO is also isoctronic with CN-"


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