[ThomasMagnus]

Hello,

I'm looking for some help on how to perform some lab calculations. We recently did a lab on the Preparation of Geometric Isomers. We were preparing the Cis and Trans isomers of butenedioic acid, i.e Fumaric and Maleic Acid. The Maleic acid was done by reacting Maleic anhydride with water, and the Fumaric acid was obtained by using the maleic acid filtrate and a reflux apparatus with HCl. Here is the data I obtained:

Maleic Anhydride Used: 4.99g
Impure Fumaric Acid: 1.24g
Pure Fumaric Acid: 0.82g
Pure Maleic Acid: 0.78g
8mL was added to the anhydride and heated at the beginning

I am supposed to calculate the theoretical yield for the experiment, but I cannot seem to find a balanced equation to use. I believe I am supposed to calculate the amount of product (fumaric+maleic) that can be produced from 4.99g of Maleic Anhydride. I also think that for every 1 mol of Maleic acid, there should be 1 mol of Fumaric produced (since they are isomers).

Is this how I would go about it?

C₄H₂O₃ + H₂O C₄H₄O₄

Calculate the amount of Maleic acid produced (using the anhydride as the limiting reagent), and since the fumaric is just an isomer, this should be the theoretical yield?

Thank you for your help

[Borek]

Sorry, but without more precise question (theoretical yield of what?) you won't get precise advice.

You can calculate yield of maleic acid in the first reaction, and yield of fumaric acid in the second. That will be two theoretical yields.

Try to draw both reactions using structural formulae first, it will help you understand what is going on.