Recently Active Questions

*Image* ----(NH4)2 Sx-----> A -----Br2/H2O ---->B ----NaNO2/Hcl---> C ----Sn/Hcl---> D ---Br2/H2O----> E Fond the total no of Br atoms present in (E) ??? ...

Kb of an acid base indicator is 10-9. The pH at which its 10-3M solution shows colour change is -------. plz provide ur method also... ...

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\\\texttt{Given\; that\;} \\H_k=\frac{k(k-1)}{2}cos\left ( \frac{k(k-1)\pi}{2} \right )\\\texttt{Find \;teh\; value}\; of\\\;H_{19}+H_{20}+H_{21}......H_{98} try it..for practice ...

If S=1+2+4+8+16+...∞.Then S is a positive number.Multiply both sides by 2,then it is found that 2S=S-1 which leads to conclusion that S=-1 which is certainly negative.Do you agree with conclusion?Give a suitable explainatio ...

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Is there any method to find time constant of L-C OR R-C etc circuits?????????????????? ...

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sir for organic i have op agarwal,morrison,arihant(the latest edition),bt material ,fiit jee rsm and some e books... I am trying questions from all these.. but where to read the theory part.I am really confused... Here everyo ...

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TRY THIS QUESTION: A recurrence satisfies a_{n+1}=a_{n}+\sqrt{1+a_{n}} then Obtain an explicit formula for a_{n} i.e. find a function f(n) such that a_{n}=F(n) (given that a_{0}=0 ) ...

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Q1. While gas from a cooking cylinder is used, pressure does not fall appreciably till the last few minutes. Why? Q2. When we place a gas cylinder on a van and the van moves, does the kinetic energy of the molecules increase? ...

hey guys can u help and tell how the differential equation has been solved here *Image* i mean can u say how they have eliminated time ? thanks [1] ...

Yesterday Philip was frustrated at the lack of gud problems...I am posting some for everyones practice..........2009 aspirants should solve them and put up solutions here for 2010 students to learn............. Some might be ...

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Q) A Square ABCD of diagonal 2a is folded along the diagonal AC so that the planes DAC and BAC are at right angles. The shortest distance between DC and AB is a) √2a b) 2/3 a c) 2/√5 a d) √3/2 a ...

Can anyone tell about Retro aldol reaction? Please I need to know it. ...

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1. .HCOOH IS ONLY MONOBASIC ACID WHICH UNDERGOES OXIDATION WITH OXIDISING AGENT .HCOOH BEHAVES AS ACID AS WELL AS ALDEHYDE 2..M.P OF FUMARIC ACID > .M.P OF MALEIC ACID MP OF SYMMETRICAL MOLECULE> UNSYMMETRICAL MOLECULE ...

1) If the normal at one end of the latus rectum of an ellipse x2/a2+y2/b2=1 passes through the one end of the minor axis then A. e4-e2+1=0 B. e2-e+1=0 C. e2+e+1=0 D. e4+e2-1=0 2) In an ellipse the eccentric angle of any point ...

64Cu(T50=12.8h) decays β- emission( 38 %),β+ emission(19%) and electron capture(43%).Write the decay products and calculate partial half-lives for each of the decay process. didnt exactly understand the q. ...

The time required for 10% completion of a first order reaction at 298 K is equal to that required for its 25 % completion at 308 K.If pre exponential factor for the reaction is 3.56 x 109s-1,calculate its rate constant at 318 ...