Bharti Vidhyapeeth University, pune!

Bharti Vidhyapeeth, Pune will be conducting CET-2010 for students willing to take Admission in their B-Tech programs on 21st May2010. It is one of the highly ranked college in India with good Placement record… And for students who are not able to qualify for IIT, NIT or other first choice institutes like BITS, Pilani .. They can try their capability in BVP-CET 2010…

BVP

Declaration of the Merit List for BVP CET 2010 will be made on 28th June 2010..

You can check about your application form status and e-Admit card issue and results here

BHARTI VIDHYAPEETH STATUS

Also,you can check for CET-MBA Results BVP CET MBA….

Nucleophilic substitution Bi-molecular!!!

This topic sometimes seems to be like a barrier for chemistry students, but it isn’t if it is studied intelligently and with fun….
So lets enjoy this topic now in style and become a part-time expert ….

Now why waste time let’s enjoy…

There are few things that I would like to share with you before you read this post.
1. I am not the real author of this post…
2. These methods of understanding organic chemistry have been developed by Ankush pathak(B-Tech)..

First of all lets know that SN2 reaction is a very basic part of organic reaction…It is very important and is frequently used in many reactions
Here “S” stands for Substitution, “N” for Nucleophilic and “2” for bi-molecular… Now you might be feeling a bit confused.. Lets make it simpler!

In SN2 reaction, the rate depends on the concentration of substrate and the reagent BOTH( hence it is called bi-molecular), Now in the example
given Cl acts as a reagent and ethanal as substrate, Now again you might be confused that what is a reagent and what is a substrate???…..
If you are not able to see the Diagram Consider chloride ion and ethanal..And make it in a copy!!
So REAGENT and SUBSTRATE are nothing but a part of our joke!!!, Let us consider a Girl and a boy,Now I ask you a question,
Who usually gives heart first???…. Your answer then will be a boy..(Like me).. So lets join both the theories together…NOW

REAGENT is same as BOY’s HEART…
SUBSTRATE is same as GIRL’s BEAUTY…

And in organic language a reagent in a SN2 reaction is a compound or a molecule that provides lone pair( BOY’s HEART) and is called
a nucleophile, whereas SUBSTRATE is a molecule that accepts lone pair and is called an electrophile( ORGANIC GIRL, she always accepts you, no demands)…Also PHILE means love,demand for romance, so a molecule which is a nuleophile wants to have a romance with nucleus whereas electrophile wants to have romance with electron(s)…so nucleophile is nucleus loving and electrophile is electron loving..

Here in this reaction Cl- is having a lone pair(nothing but a pair of electron, so now you know who would be calling it for romance..”THE ORGANIC GIRL Ethanal”..) here the role of organic girl is played by ETHANAL( which in turn is called for romance by Cl- , a nucleophile)….And ultimately
you know what will happen if Ethanal forgot to take the PILL…..

When both Girl and boy are ready then what’s the problem let’s enjoy!!

Here as shown in the Diagram Cl Provides the lone pair and Ethanal accepts it…..The product of the reaction is nothing but simply an chloro alcohol as shown in the figure below in presence of an acid……And the reaction comes to a funny End giving birth to an alcoholic child in the Hospital..

Now if you liked this post from Ankush pathak, if you wish to have a future reference to organic topic like this subscribe to
SHASHAco. Simple Tips….

With regards!!

Those who want to win!!

Hey! mathematicians who probably think that they have excelled in certain topics,surely would not be knowing this trick which i am going to discuss, do you have a guess? NO!


WARNING!


IN this article i have got something useful for all! OH! sorry only for Mathematicians.

You might be a expert in calculus or in algebra or even in geometry, trigonometry or so statistics but this post is for those who possibly find maths difficult when it comes to solving problems. Now for those who find calculus difficult, i have a perfect site for them, i would probably say  it is the best site right now in the network, which explains the basic of calculus in the efficient and intellectual way, what to say even an average student like me can understand. So what you are waiting for have a look at CALCULUS MADE EASY, but my dear friends now why to waste your time!, here is specially for you only, a trick to solve questions in which you probably are asked to give the value for the expressions made up of trigonometrical representations for a triangle and such questions are believed to be based on “solution of triangles” or “properties of triangle”.

For Instance lets take an example, Find the value of

(a/c) sin2C + (c/a)sin2A. In This question a,c represent the sides of the triangle apposite to angle A and angle C respectively, as shown in the diagram below

General Triangle

Now to find the value for such expressions, some books or probably all books recommend to learn lengthy formulas for trigonometrical angles Like Sin(A/2) =((s-a)(s-b)/bc)1/2

Where s  is called the semi perimeter of the triangle such that 2s = (a+ b+c), is the sum of lengths of sides of the triangle.

Now as i have promised you in the starting of the post to tell you the trick, here it is

For  sides a, c in the above example put a,c =1 and the angle A and angle C = 600

That is simply consider the triangle as an equilateral triangle then putting the values  in the above example we get something like this (1/1)sin1200 + (1/1)sin1200 = 31/2

Personally i find this method as the best method to solve such type of questions if i have less time, but i would recommend to check your value using general method by putting in the formulas  for sin2C and sin2A , but obviously this is write method.

Here are few questions that you can attempt now,

Find the value for

  1. (b/a)sin2A + (a/b)sin2B =
  2. In a triangle ABC if, a, b, c are in A.P and cos$1 =( a/b+c) and cos$2 =(b/a+c) and cos$3=(c/a+b) , where $1,$2,$3 are angles then find the value of: tan2($1/2) +tan2($3/2)=

The answers to these question are 31/2 and 2/3, if you have got the answers you are on the way to success!!!

Have fun

With Regards!

Difference Between Solubility Product And Ionic Product??

All those who want to understand the basics of Ionic Equilibrium here is topic which you usually do not find in books , but this question is frequently asked in the exams and even in the Board viva …

So what is the Difference between Ionic product and Solubility product…

Let us consider a reaction, a reversible reaction in which silver chloride(Agcl) dissociates into chloride ion(Cl-) and silver ion(Ag+)..

AgCl <=====> (Ag+)  + ( Cl-)

Let initially at time t=0 , AgCl has concentration =a molar or a M (where M stands for molarity)… to know a bit more about molarity as of now visit www.molarity.com

Now suppose after time t=t1 seconds AgCl has dissociated to give the respective ions , now the concentration are as follows…

[AgCl]= a-x M , [Cl-]= x M , [Ag+]=x M ….

Now if we are asked to write the ionic product we simply write it down as [Cl-][Ag+]= x.x

but at the same time if the teacher asks to write solubility product you will say it is not possible right now to do so.. We can only define solubility product when the solution is Saturated…

NOW What is this Saturated solution??? .. Simple it is solution in which the rate of dissociation of salt (in the above example AgCl) is equal to the rate of association of ions (in the above example Cl- and Ag+) to form back the salt or compound… or you can say no more of salt or compound can be added to the solution , if you tried doing so you will get the same amount of salt thrown on your face by the solution through the process called precipitation..to know more about saturated solution visit www.saturatedhaina.com….

Hence , Solubility product is same as ionic product but it is defined only when the solution is saturated….

Wishing you success in advance for your exams!!!!

With regards!!

Some Basics of Distance -time graph!!!

Distance-Time Graph is a graph where Y-axis represents distance traveled and X-axis represents time….
What we can determine from Distance-time graph?
1. We can determine the velocity( whether it is increasing or decreasing at a given moment)…
2. We can determine the Displacement…
3.We can determine the time taken to cover a given distance and so on………

//Let us Discuss very important part of Distance-time graph//

How to determine from a distance- time, that whether the velocity related to distance time curve is increasing or decreasing ?

For all this stuff you need to clear two of the very important concepts…

1.Tangent function is an increasing function in the interval [- 1.57,1.57] => [0,1.57], a tangent function is nothing but tan@
(where @ is nothing but the angle in degrees), this usually we all study in the basic trigonometry in our junior classes
but to know a bit more about tangent function visit www.indiantan.com……


For your simplicity let me explain it to you in a simpler way all of you ,i suppose know that tan0=0 ,tan30=(1/3)1/2
and tan45=1 ,and tan60=(3)1/2, tan90=infinite… from all this you all can easily determine that as 90>60>45>30>0
tan90>tan60>tan45>tan30>tan0.. it implies tan@ is an increasing function….


2. A concave up curve is a curve shaped like a bowl whose hole is in the upward direction and Concave down is similarly
a curve whose hole is pointing in the downward direction……..

Now how to determine whether the velocity is increasing or decreasing from the given Distance-time curve….

CONSIDER THESE GRAPHS

Consider the two curve shown (a) is a concave upward curve and(b) is a concave downward curve , now consider the
angles shown in the graph(a) as you can determine from the graph that angle a < b < c therefore tana< tanb < tanc …
now you need to know that dx/dt that is ( ratio of differential change in distance to the differential change in time)..is nothing but
the tangent drawn to the curve at that point and that in turn is nothing but the velocity at that point ,so as the tangent function is
increasing therefore velocity is increasing ,similarly in the graph(b) the tangent function is decreasing and henceforth the velocity
is decreasing…..

So one thing you need to REMEMBER BY HEART is that a concave upward curve in a distance-time graph represents the INCREASING
VELOCITY and concave downward represents the DECREASING VELOCITY….

Also from the graph(a) determine that at a point p velocity is nothing but the tangent at that point..to know more about tangent to a curve visit
www.tangentcurve.com

With regards!!!

Wishing you success for your exams…
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Have fun/……