Limiting Reactants

[Madison Hurst]

When finding limiting reagents, how do you know what product to compare moles to if not directly stated in the problem? I noticed several module problems that said what is the limiting reactant for the product created? However, there was more than one product in the reaction.

[Chem_Mod]

Think about it: Say you have the reaction A+B -> C+D. Say you calculated how many grams of C could be made from A and find that it is less than the grams of C that could be produced by B. This means that A is the limiting reactant. Do you think the grams of D that could be produced by C would be greater or less than the grams of D that could be produced by B?

[405112316]

Either product can be used to understand which reactant is limiting. The moles and of product are always proportional to each other, and they both rely on the same limiting reactant to determine how much is produced.

[Hadji Yono-Cruz 2L]

You can use either of the products to find the limiting reactant. Just make sure that you use the same product (does not matter which you choose) when comparing the reactants. However, on a test the next subquestion might ask about a specific product, so it may be more beneficial to choose that one instead. Generally, it does not matter which product you choose.