disiamylborane adds to a triple bond to give an alkenylborane. upon oxidation with oh–, h2o2, the alkenylborane will form an enol that tautomerizes to an aldehyde. in the first box below, draw the mechanism arrows for the reaction of disiamylborane with the alkyne, and in the last box draw the structure of the aldehyde.

a is the answer to this question

explanation:

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol