My research involves understanding the enzymes that act on the substrate dimethy

Question

My research involves understanding the enzymes that act on the substrate dimethylsulfone (Lewis structure depicted below). My current hypothesis is that the carbon-sulfur bond of dimethylsulfone is broken and the products formed are the ones depicted below. Formally, this reaction also requires molecular oxygen and molecular hydrogen as reactants. Use average bond energies to estimate the ?Hrxn for this balanced reaction. The average bond dissociation energy for a carbon-sulfur bond is 699 kJ/mol.

2. Based on the estimated ?Hrxn, would you predict that this reaction is endothermic or exothermic?

Explanation / Answer

Broken bonds:

S-O, S- C, C-H, H-H, O=O ----> 87 kcal/mol + 65 kcal/mol + 99 kcal/mol + 104.2 kcal/mol + 119 kcal/mol

Broken bonds= 474.2 kcal/mol

Formed bonds:

3 O-H, C=O ----> 3 x (111 kcal/mol) + 177 kcal/mol = 510 kcal/mol

DHrxn= broken - formed = 474.2 kcal/mol - 510 kcal/mol = -35.8 kcal/mol

When the DHrxn is negative the reaction is exothermic.

Related Questions

Navigate

• Browse (All)
• Browse M
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.