Dihydroxyacetone is a component of quick tanning lotions. (It reacts with the amino acids in the upper layer of skin and colors them brown in a reaction similar to that occurring when food is browned as it cooks.)
(a) Use bond dissociation enthalpies to estimate the enthalpy change for the following reaction. Is the reaction exothermic or endothermic?

(b) Are dihydroxyacetone and acetone polar molecules?
(c) A proton (H⁺) can be removed from a molecule of dihydroxyacetone with strong bases (which is in part what happens in the tanning reaction). Which H atoms are the most positive in dihydroxyacetone?

Transcribed Image Text:

H:0: H HC-C-C-H + 0₂ H H Acetone H :0: H -C- H H Dihydroxyacetone H-0 -0-H