1RCO- ??????????
"nucleophilicity runs parallel to basicity when the nucleophilic atom is the same in various species"
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1u are just considering the negative charge !!
but there are other things too !
1good then how can we arrange these chemistry things in increasing order of their nucleophilicity ? :D
RCOO- , RO- , ROH , RCOOH
1Basicity F- > Cl- > Br- > I-
Leaving ability I- > Br- > Cl- > F-
Higher basicity, lower leaving ability
a nucleophile which has lower leaving ability will replace a nucleophile with higher leaving ability
a nucleophile which has higher nucleophilicity will replace a nucleophile with lower nucleophilicity.
a nucleophile which has higher basicity will replace a nucleophile with lower basicity
This is because more basic anion will have more negative charge on the nucleophilic atom. Eg. CH3OH is a stronger acid than C2H5OH because CH3O- is more stable than C2H5O- . (+I effect of C2H5 is more than CH3 group). Therefore C2H5O- is stronger base than CH3O- (Conjugate base of weaker acid is stronger). CH3O- has higher leaving ability than C2H5O-. C2H5O- has more electron density on O due to more +I effect compared to CH3O- .
11Well, unique. That maybe bcos CCl2 (or more formally :CCl2[3]) has two eletcrons less than the configuration it was comfortable with [1]
1thats a unique thinking dude !!
then why is CCl2 a electrophile even though it has a lone pair of electrons ?
3when the electrostatic force of repulsion is greater the electrons have more tendency to get away from the atom because the electrostatic force is predominantly higher
1hey dai poyi urgan Unique Jinesh ..........nee poo monee dinesha..........
1"nucleophilicity or basicity arises when the electrostatic force of repulsion is greater than that of the electrostatic force of attraction"
can u elaborate this sankara ?
3i thot dat the discussion can be done by considering as ions.
nucleophilicity or basicity arises when the electrostatic force of repulsion is greater than that of the electrostatic force of attraction
please reply if i was wrong
3unique anna
in case of RCOO- the negative charge will be shared by the oxygen atom over a larger area which means dat the molecule is having a less charge per unit area
in case of RO- the charge on the oxygen atm is predominately higher and it will be like 
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1ha prateek !... its one and the same thing !!... well done buddies !!
shall we move on to another one ?
1sankara !!..thats very true !!
the O is just so mean to have the electrons with him !!... selfish girl ..hehe
so its rite sankara .........
3unique anna i have given the same ans
whle typing i have left the R letter
1might be due to resonance the charge on O gets delocalized and the charge is distributed among two O becoz of whcih the electron density decreases....
and therefore electron density of RO- greater as compared to RCOO-
1becaz C0 bond is much more stronger than R0 bonds is that correct unique
1prateek i was just expecting this answer ... which is wrong !
but sankara what about the charge density on RCOO- ..why do u think it is less than that of RO- ?