A compound with molecular formula C 4 H 10 O 3 in converted by the action of acetyl chloride to a compound of molecular mass 190. The original compound C 4 H 10 O 3 has how many - OH groups?

Step-by-step solution

In acetylation, replacement of H of O - H occurs by C H 3 C O - group. - O - H + C l C | | O - C H 3 → - O C O C H 3 + H C l i.e., H atom of mass 1 amu is lost and an acetyl group of mass 43 amu is added. Thus, there is a net gain of 43 - 1 = 42 amu for every acetyl group introduced. Mass of difference of final product and original compound is 190 - 106 = 84. Hence, number of - O H groups = 84 42 = 2 .