The Wolff–Kishner reaction uses hydrazine (H2NNH2) and hydroxide (–OH) to reduce a carbonyl to the alkane. The first steps of the mechanism convert a carbonyl to a hydrazone in a manner similar to imine formation. Draw the mechanism arrows for the reaction from the hydrazone to the alkane. Be sure to add lone pairs of electrons and nonzero formal charges to all species.

i would say b

explanation:

but i think i would need more information than that

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