`S_N1` /`S_N2` proceeds through the formation of a carbocation .

Out of S_N1 and S_N2 , which reaction occurs with Racemisation.

Out of S_N1 and S_N2 , which reaction occurs with Inversion of configuration.

Let S_1, S_2, be squares such that for each ngeq1, the length of a side of S_n equals the length of a diagonal of S_(n+1)dot If the length of a side of S_1 is 10cm , then the least value of n is the area of S_n less than 1 sq. cm?

Let S be the sum, P the product and R the sum of reciprocals of n terms in a G.P. Prove that P^2R^n = S^n .

Let S be the sum, P the product and R the sum of reciprocals of n terms in a G.P. Prove that P^(2)R^(n) = S^(n) .

S_N2 reaction occurs with inversion of configuration/ racemisation.

A sphere S_1 of radius r_1 encloses a charge Q. If there is another concentric sphere S_2 of the radius r_2(r_2>r_1) and there be no additional charges between S_1 and S_2 find the ratio of electric flux through S_1 and S_2

If hydrogen atoms (in the ground state ) are passed through an homogeneous magnetic field, the beam is split into two parts. This interaction with the magnetic field shows that the atoms must have magnetic moment. However, the moment cannot be due to the orbital angular momentum since l=0. Hence one must assume existence of intrinsic angular momentum, which as the experiment shows, has only two permitted orientations. Spin of the electron produce angular momentum equal to S=sqrt(s(s+1))(h)/(2pi) where S=+(1)/(2) . Total spin of an atom = +(n)/(2) " or "-(n)/(2) where n is the number of unpaired electrons. The substance which contain species with unpaired electrons in their orbitals behave as paramagnetic substances. The paramagnetism is expressed in terms of magnetic moment. The magnetic moment of an atom mu_(s)sqrt(s(s+1))(eh)/(2pimc)=sqrt((n)/(2)((n)/(2)+1))(eh)/(2pimc)" "s=(n)/(2) impliesmu_(s)=sqrt(n(n+1)) B.M. 1. B.M. (Bohr magneton)= (eh)/(4pimc) If magnetic moment is zero the substance is diamagnetic. Which of the following ion has lowest magnetic moment?

A conducting sphere S_1 of radius r is attached to an insulating handle. Another conduction sphere S_2 of radius R is mounted on an insulating stand. S_2 is initially uncharged. S_1 is given a charge Q brought into contact with S_2 and removed. S_1 is recharge such that the charge on it is again Q and it is again brought into contact with S_2 and removed. This procedure is repeated n times. Find the electrostatic energy of S_2 after n such contacts with S_1 .