How do you find the amount in moles of excess reactant that reamins
Please retype that, minding your spelling.
=)
Can you please show me how to determine the amount in moles of excess reactant that remains
Sorry about the mistakes =)
This is part of an excess reagent problem. Please post your question in full. It is much easier to work with an example than to try and talk you through a hypothetical problem. But here are the steps.
Step 1. Write a balanced equation.
Step 2. Convert what you have to mols remembering that mols = grams/molar mass. We will call this step 2a and step 2b. You will have two of more mols.
Step 3.
a. Using the equation, use the coefficients to convert mols of 2a into mols of the product.
b. Using the equation, use the coefficients to convert mols of 2b into mols of the product.
Step 4. The smaller number of mols will be the correct number of mols of product formed and that reagent will be the limiting reagent.
Step 4. Knowing the limiting reagent, convert mols of it to mols of the OTHER reagent. Use the coefficients from the balanced equation to do this. This will tell you the number of mols of the non-limiting reagent used in the reaction.
Step 5. Now subtract the initial number of mols of the OTHER reagent from the mols that will react and the answer will be the number of mols of the reagent remaining unreacted.
I know this sounds daunting; however, it looks much simpler with a real example.
Please post your problem, if you still have trouble with it, along with your work, and tell us exactly what you don't understand about it.
I posted the sample problem above
Apologies for the confusion. Let's work through an example to understand how to determine the amount in moles of excess reactant that remains.
Example:
Suppose we have the reaction: 2A + 3B -> C
Given:
- We have 10 moles of A and 15 moles of B.
- The balanced equation suggests that 2 moles of A react with 3 moles of B to produce 1 mole of C.
To find the limiting reactant (the reactant that will be completely consumed):
Step 1: Convert the given quantities to moles using the mols = grams/molar mass equation.
Step 2: Perform the stoichiometric conversion to determine the limiting reactant.
a. For A: 10 moles of A x (3 moles of B / 2 moles of A) = 15 moles of B required
b. For B: 15 moles of B x (2 moles of A / 3 moles of B) = 10 moles of A required
Step 3: Compare the amounts of A and B required. We see that both reactants are required in equal amounts. Thus, neither A nor B is in excess, and both will be completely consumed.
To find the amount in moles of excess reactant that remains:
In this case, since both reactants are fully consumed, there is no excess reactant remaining.
It's important to note that if there were an excess of reactant, you would follow these additional steps:
Step 4: Determine the amount of the non-limiting reactant that reacted. Use the stoichiometric coefficients from the balanced equation.
Step 5: Subtract the amount of non-limiting reactant used from the initial amount to find the amount of excess reactant remaining.
I hope this example helps clarify how to determine the amount in moles of excess reactant that remains. If you have any further questions, please let me know.