(a) What does the term diamagnetism mean? (b) How doesa diamagnetic substance respond to a magnetic field?(c) Which of the following ions would you expect to bediamagnetic: N22 -, O22 -, Be22 + , C2-?

[o Consider the reaction scheme below. Me Me of 210 210 COMI20 OH Hola Holensal,d bus 9 (ii) Explain briefly the observed regioselectivity. Iviz gniw 11 toshsvo beiniinoo noitz9 H® (cat.) With reference to the following reaction scheme: [monqo 1250 901 ayawis luna no br Me NaBH4, Et₂O (i) Draw a curved arrow mechanism to explain the transformation of 9 into 10. of main Me 101 anoitiba Ho HO Me, O Me 10 100 10 Stone & arq tot abortom saogo atowens 1004 Viitzut vford bre ooort mott gnis2 H) osogor (1) Me Miel Me 12 * OH (i) Draw Newman projections for the two lowest energy conformations of ketone 11. (ii) Considering your answer to part (i), identify which is the most reactive conformation of 11 and explain your choice. (iii) Indicate the stereochemistry (at C*) of the major diastereoisomer of alcohol 12. Use appropriate strereochemical drawings to explain your answer.

draw structures of the following cations and determine their point groups: 1. Diamagnetic[Ni(CN)4]2- 2..Paramagnetic[NiCl4]2

Calculate in units of deltaₒ, the LFSE for the octahedral ions below in their high-spins state.           (a) Mn3+                                                 (b) Co3+