Question

Question 1: Using Hard/Soft Acid/Base Concepts (HSAB) please decribe the following

a) Dimethylmercury, Hg(CH3)2, is one of the strongest known neurotoxins. Is it safe to mix mercuric fluoride, HgF2, with methyl lithium, LiCH3? Explain your decision.

b) Dimethylmagnesium, Mg(CH3)2, reacts violently with water, while Hg(CH3)2 is remarkably stable in aqueous environment. Explain this observation and provide a chemical equation for the reaction involving Mg(CH3)2.

Answer 1

Question 1: Using Hard/Soft Acid/Base Concepts (HSAB) please decribe the following
a) Dimethylmercury, Hg(CH3)2, is one of the strongest known neurotoxins. Is it safe to mix mercuric fluoride, HgF2, with methyl lithium, LiCH3? Explain your decision.

LiCH3 + HgF2 ------------- Hg(CH3)2 + 2LiF

not safe because there reaction will takes place. as in LiCH3 is the combination of hard -soft and similarly HgF2 is the combination of hard -soft acid base. but there product will produce hard-hard and soft-soft combination, which is stable according to HSAB theory. here Hg+2 is a soft acid it try to combine with soft base CH3-. similarly F- is hard base it will accept hard acid Li+

b) Dimethylmagnesium, Mg(CH3)2, reacts violently with water, while Hg(CH3)2 is remarkably stable in aqueous environment. Explain this observation and provide a chemical equation for the reaction involving Mg(CH3)2.

Mg(CH3)2 reacts violently with water, because which is the combination of hard acid and soft base. but ther product is the combination of hard acid(Mg+2) and hard base(OH-), soft acid(H+) soft base(CH3-). thats why it reacts violenly with water.

Mg(CH3)2 + 2H2O ------------- Mg(OH)2 + 2CH4

while Hg(CH3)2 is remarkably stable in aqueous environment cause in this compound Hg(CH3)2 alredy soft-soft combination present , which is stable according to HSAB theory. here Hg+2 is a soft acid it try to combine with soft base CH3-. thats why it is stable remarkbly in aqueous medium.