A 2.92 g (27.0 mmol) sample of phenylhydrazine was dissolved in 10 mL of 95% ethanol and stirred while 3.30 g (27.0 mmol) of salicylaldehyde, dissolved in 15 mL of ethanol, was added. what is the theoretical yield in grams for salicylaldehyde phenylhydrazone?

Explanation:

Hello,

In this case, the undergoing chemical reaction is shown on the attached picture, in which you can see that phenylhydrazine reacts with salicylaldehyde to yield salicylaldehyde phenylhydrazone.

In such a way, considering that just the moles of the reagents are important to identify the limiting reagent and subsequently the theoretical amount of salicylaldehyde phenylhydrazone, one proceeds as follows:

Therefore, since all of the reagents are consumed, one computes the theoretical yield of the product as shown below considering its molar mass of 212.253 g/mol or 212.253mg/mmol which is the same:

Best regards.

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.