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Catalogs Discussion Forums -> Lounge -> BDAY greetings -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Happy bday bro !

Catalogs Discussion Forums -> Mechanics -> projectiles on an inclined plane -> Go to message
This Post 15 points    (Olaaa!! Perrrfect answer.   in 3 votes )   [?]

It is not different from the ordinary projectile motion,except that the vectors are resolved along the chosen axes


Let the angle of inclination of the incline be  and the angle of projection to be  with respect to the ground.

v=velocity of the projectile

 


Consider two axes X,Y along and perpendicular to the incline



Along X axis








Along Yaxis







 

Write the equations of motion along X and Y axes




Community shelf Community shelf -> GoIIT in 2020 -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
coo! :)
Catalogs Discussion Forums -> Physical Chemistry -> What do we actually mean by Order of any reaction -informallly -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

Consider any reaction



The order of the reaction wrt A or B shows how the change in concentration of either A or B will affect the rate of the reaction.


If the rate of reactoin is directly proportional to the concentration of A,then



If the rate of reactoin is directly proportional to the square of concentration of A,then



Thus for the given reaction,



if  


order of the reaction wrt A is a, order of reaction wrt  B is b


The overall order of reaction= a+b [obtained by summing up the individual orders] wrt to the reactants involved

Catalogs Discussion Forums -> Integral Calculus -> Integrate - Using the shortest possible no of steps -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
hey ppl...!

atleast try completing the sum...

(note the word completing..!)

n as i have said...m luking fr any "simple trick" which these kind of qs usually have to crack them n leave ppl surprised !
Catalogs Discussion Forums -> Integral Calculus -> Integrate - Using the shortest possible no of steps -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

It more or less resembles my procedure....which no doubt isnt that short...




 


it gives the ans




 





 





 


 




 


(which no way resembles the given ans)

Catalogs Discussion Forums -> Integral Calculus -> Integrate - Using the shortest possible no of steps -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

is it??



(forgive me if it is!...m a beginner at integration..!)



 

Catalogs Discussion Forums -> Integral Calculus -> Integrate - Using the shortest possible no of steps -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Any right ans / genuine attempt is accepted ! :)



(P.S- shd have least poss no of steps)

Catalogs Discussion Forums -> Integral Calculus -> Integrate - Using the shortest possible no of steps -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]


 






 


Ans: Click here


 




 

Catalogs Discussion Forums -> General -> BITSAT mock test papers from Brilliant Tutorials -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
Thank you sir !!!
Catalogs Discussion Forums -> Physical Chemistry -> compounds structure.. -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

 


 


Carbon disulphide





Carbon disulfide   







 









Aniline



 



Aniline








Aniline

Catalogs Discussion Forums -> Lounge -> Happy Birthday deedee !! :) -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]


Happy Birthday dear :) :) :)


Community shelf Community shelf -> Organic reagents...[celebrating my first anniversary as a goIITian :) ] -> Go to message
This Post 60 points    (12 Olaaa!! Perrrfect answer.   in 12 votes )   [?]

I would thank the administration and moderation team and ofc all my dear goiitians for helping me in every possible way during my year stay at goIIT....


Hope this article might be of some help to you

 
























































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































 








 






Reagent/Catalyst






Uses






1






 Adam's Catalyst or PtO2




 






 .Hydrogenation,




.Hydrogenolysis,




.Dehydrogenation




.Oxidation reactions.




*Hydrogenation occurs with syn-stereochemistry when used on an alkyne, resulting in a cis-alkene. 






2






 Adkin's catalyst or Copper chromite/ Copper chromium oxide catalyst






 .Reduction




.Dehydrogenation




.Decarboxylation






3






  Anhydrous aluminium chloride




 




 .As catalyst in FC reactions




.In Fries rearrangement




.In gattermann reactions




.As catalyst in addition of RX across olefinic double bond




.As a catalyst in isomerisation reactions of alkane.






4






 




Bu3SnH or tributyl tin hydride or tributylstannane






  .To reduce one halogen atom of gem dihalide but does not reduce alkyl halides




. To transform acid chlorides to aldehydes






5






 




 Aluminium isopropoxide






.As a catalyst in MPV reduction




.With excess reagent and at higher temperature to transform diaryl ketone into hydrocarbon




.In oppenauer oxidation






6










Baeyer's reagent or cold alkaline solution of KMnO4




.To test the presence of unsaturation




.To cause cis-hydroxylation of double bonds






7






 9-BBN






 




.To carry out high regeoselective hydroboration




.To convert aldehyde or ketone to an alkene indirectly




 






8






 








BF3






.For FC reactions. Though it is less reactive than AlCl3, but it serves as a good catalyst for electrophilic reagents such as alcohols







boron trifluoride etherate catalyses reduction of ester by LiAlH4




. To catalyse formation of esters from alcohols, acids, ethers, olefins, etc.




.To catalyse formation of acids from alcohols




. To carry hydrolysis of cyanides to amides






9






 




NBS




.As a brominating agent at allylic and benzylic positons




.As an oxidising agent to oxidise primary and secondary alcohols to aldehydes and ketones respectively alpha-amino acids, peptides and proteins are decarboxylated with NBS in aqueous medium




RCH(NH2)COOH ---(NBS)----> RCHO + NH3 + CO2






10






Burgess reagent or Methyl N-(triethylammoniumsulphonyl)carbamate






.To convert unsubstituted amides to nitriles




. To dehydrate alcohols with syn-elimination






11






m-Chloroperbenzoic acid or mCPBA




.In B-V oxidation to convert aldehydes or ketones to acids or esters respectively




.To convert olefins to epoxides




. To convert sulphides to sulphoxides






12




Collin's reagent or Dipyridine Cr(IV) oxide...solid chromic anhydride and pyridine are dissolved in methylene chloride






. To oxidise primary alcohols to aldehydes without converting to the acids






13






 




 Collman's reagent or sodium tetracarbonyl ferrate(II)






. To convert alkyl halides, primary bromides to aldehydes. The reaction is not satisfactory for benzylic bromide.








 RBr -----(Collman's reagent, Ph3P, AcOH)----> RCHO






14






 








Diaomethane






. To methylate acidic substances like carboxylic acids. Mild acidic substances like phenol can also be methylated. However, alcohols, amines can be methylated in presence of catalyst.




.To prepare higher homologue of aldehydes and ketones.







.Cyclic ketones undergo ring expansion.






15






 








Dicyclohexylcarbodiimide or DCC






. To catalyse peptide bond formation




. To prepare alkyl aryl ethers




. To prepare diacyl peroxide from carboxylic acid in presence of H2O2. In absence of H2O2, however, acid anhydride is formed.






16






Fenton's reagent or ferrous sulphate dissolved in H2O2






.To cause hydroxylation of arenes in a radical substitution




. To cause oxidation of glycol to glycolaldehyde




.To oxidise alpha-hydroxy acids to alpha-keto acids







 in waste treatment (toxic substances hydrology
progamme). It can destroy organic compounds present in water.




 






17










Gillman reagent or lithium dialkyl copper






. To prepare unsymmetrical alkane conveniently in Corey-House reaction




. To cause alkylation of ketones as Gilman reagents do not react with ketone






18










Girard's reagent














.To form water soluble hydrazones.




these hydrazones are water soluble because of the ionic part. This property makes Girard reagent potentially effective for isolation of carbonyls from mixture soluble in non-polar solvents.






 






19




Grignard reagent






.It reacts with a variety of carbonyl derivatives




.Reacts with other various electrophiles


 




20




 Jones reagent or solution of sodium dichromate in dilute sulphuric acid.




.To cause oxidation of secondary alcohol to ketone without affecting double or triple bonds






 






21




Lead tetra acetate




.To oxidise quinol to quinone




. To oxidise 1,2-diols to aldehydes, ketones or both depending upon the structure.







in oxidation of alpha-hydroxy acids and alpha-keto acids to
give aldehydes and acids respectively with the evolution of CO2




.In oxidation of alpha-hydroxy ketones.






 






22




 Lemieux reagent or aq. solution of NaIO4 and traces of KMnO4. Actual oxidising agent is MnO4(-)






.To determine position of a double bond. Olefinic bond is oxidised to carbonyls or acids or both depending upon situation






 






23






Lindlar catalyst or palladium deposited on CaCO3




.For the hydrogenation of alkynes to alkenes. Alkyne reduction is stereoselective, occuring via syn-addition to give cis-alkene.






 






24






LAH or LiAlH4/ lithium aluminium hydride




.To reduce carbonyl compounds, acids, esters, epoxides, acid chlorides and anhydrides to alcohols without normally affecting the double bond. However, the double bond gets reduced when a phenyl group is present at beta- position.




.to reduce nitro compounds, oximes, and azides to primary amines. When LAH is added to the solution of nitrile at low temperature, aldehyde is formed. But when solution of nitrile is added to LAH, amine is formed.




.To reduce primary and secondary halides. However, tertiary halides give olefins due to elimination.






 






25




Lucas reagent or solution of anhydrous ZnCl2 in conc. HCl




.To distinguish b/w primary, secondary and tertiary alcohols.






 






26






MnO2 used in methylene chloride medium




.To oxidise allylic and propargylic alcohols




to reactive aldehydes




.To convert cyanides to amides






 






27




Organolithium reagent or RLi




.To prepare highly hindered alcohols, which is not possible through grignard's reagent. Highly hindered grignard's reagents undergo reduction.






 






28






  Osmium  tetroxide




 . To convert an alkene to vicinal diol through syn-addition






 






29






 




Periodic acid or ortho periodic acid.






White crystalline inorganic solid used in water medium. Almost behaves in a similar way as Pb(OAc)4. However, it is complementory to Pb(OAc)4, which is soluble in organic solvents.







.To cause oxidative cleavage of bonds carrying groups
prone to undergo oxidation. One mole of reagent is required to cleave one bond.




.To cleave epoxides to aldehydes.






 






30




Raney nickel




.As a reagent to desulphurise organic compounds







.For reduction of carbon-carbon multiple bonds







.For reduction of aromatic ethers







.For reduction of nitro group to amino group







 .For hardening of oils






 






31






 




Schiff's reagent:: it is a dilute solution of p-rosaniline hydrochloride decolourised by SO2






.To test the presence of CHO functional group in an organic material. Aldehydes snatch a molecule of sulphurous acid from schiff's reagent to restore its quinoid structure and hence pink colour. Ketones do not react.






 






32






 




Sodamide (NaNH2)




. To prepare alkynes from dihalides







.To convert lower 1-alkynes to higher alkynes







.To prepare reactive anions, which can take part in a
number of reactions






 






33






NaBH4 used in alkaline medium or in DMSO













 . To reduce carbonyl group to alcohol without affecting other reducible groups such as ester, carboxyl, amide, nitrile, nitro and double bond




.To reduce an ozonide to an alcohol




. To reduce primary, secondary and tertiary alkyl halides.



 


Source:Internet

Catalogs Discussion Forums -> Organic Chemistry -> difference between stereo centre and chiralcentre -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

chiral center or stereo center or stereogenic center are the names given to an atom


connected to four different atoms or four different Subsituent  groups

Catalogs Discussion Forums -> Differential Calculus -> Application of derivative -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

From the definition of a derivative,





  





we need to find the value of   




let f(x)=cos x