Messages posted by Arushi Gupta

ok....it is a method of partial reduction of cyanides to aldehydes.

SnCl2 + 2 HCl ---> SnCl4 + 2 H

CH3--CN + 2 H (HCl)------> CH3----CH==NH.HCl (boiling water)-------> CH3CHO + NH4Cl

HCl and boling water written in brackets are to be written above arrows

did u mean Stephen Reduction ?

1 cal = 4.2 J
therefore, 1 J = 1/4.2 = 0.24 cal

very nice....liked 5th and 15th the most :)

very nice....liked 5th and 15th the most :)

me too in the same problem :/

does anybody know a way out ?

ok....thank u !

nd should i post the second ques again ?

ok...thanx !

Q : Calculate the uncertainity in the velocity of a wagon of mass 2000 kg whose positions is known to an accuracy of +-10m.(plus minus 10 m )

The ans is given according to Heisenberg's uncertainity Principle but how can it be used since it is not applicable at macroscopic level ?

A compound of vanadium has a magnetic moment of 1.73 BM. Work out the electronic configuration of the vanadium in the compound.

1.)

A series of lines in the spectrum of atomic hydrogen lies at wavelenghts 856.46, 482.7, 434.17, 410.29 nm. What is the wavelength of next line in the series ?

2.)

Calculate the velocity of an electron placed in the second orbit of the Li 2+ ion. Also calculate the number of revolutions per second that it makes around the nucleus.

A rigid uniform triangular frame ABC of mass m is hanging from a rigid long horizontal road PQ. The frame is constrained to move along horizontal without fiction. A bead of mass m is released from B that moves along BC.What is the displacement of the frame when the bead reaches C ?

I think harry is talking about " MCQ Mathematics by A Das Gupta"

m sry 4 my stupidity....i got d ans

Evaluate the following Limit

this is of the form 0/0 nd can be easily solved by L.Hospital's Rule to get the ans 11/4

but if i solve it by NCERT method i.e. by cancelling common factors, m not getting the ans....plz correct me

thanx everybody.....i got it :)

and @ashankrudola.....the other 2 vertices r not given to b the end points of latus rectum...

The questions says:
Complete the following reaction and give its mechanism in short.
My doubt is whether rather how will the reaction happen..?? As far as I know ,reaction of alcohols with acid chlorides takes place in presence of base catalyst!The hydrogen of the hydroxyl group is replaced by an acyl group (RCO-),resulting in the formation of esters.
But in the above reaction the question asks for the reaction to be carried out in acidic medium...
Can anyone give suitable mechanism for this with reasons?

Why H+ is not attacking the C=O in spite of formation of allylic carbo-cation (more stable than 2 degree carbo-cation) ?

An equilateral triangle is inscribed in the parabola "y square = 4ax" , where one vertex is at the vertex of the parabola. Find the length of the side of the triangle.

iitd or CBSE ?

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