Answer to Question #156573 in General Chemistry for NEEL THAKKAR

Question

Que 1. State Pauli’s exclusion principle and show that the maximum number of electrons in a given shell is 2n2 where n is the principal quantum number. Mention all values of different quantum numbers when n = 6.

Que 2. (1) Explain carefully why exactly half-filled and completely filled orbitals are more stable than other orbitals. Illustrate with suitable examples. (2) Calculate the uncertainty in the velocity of a bullet weighing 10 g whose position is known with an accuracy of ±0.1 nm. h = 6.626 x 10-34 Js.

Answer 1

The pattern of maximum possible electrons = 2n2 is correct..

2. 1) The orbitals in which the sub-shell is exactly half-filled or completely filled are more stable because of the symmetrical distribution of electrons. Exchange energy: The electrons which are there in degenerate orbitals have a parallel spin and tend to exchange their position..

2) Heisenberg uncertainity principle △p.△x≥4x
h​m△v.△x≥4x
h​m≥4z△v△x
h​△v≥4zm△x
h​4×3.14×10×10−3×0.01×10−3
6.628×10−34​
=5.27×10−28m/s