limiting reagent

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elz787

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is there an easy way to find the limiting reagent ?

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elz787 said:
is there an easy way to find the limiting reagent ?

based on the balanced equation look at how many moles of each reactant is listed, and then convert however many grams of each reagent youre using in the problem, and then look at the mole ratio from the balanced equation..

say H2 + 1/2 O2 = H2O

Then you know Hydrogen is your limiting reagent
 
ya thought so, but theres no way to tell by just eyeballing it right?
 
elz787 said:
ya thought so, but theres no way to tell by just eyeballing it right?

if youve seen the reaction before in lab or something....and you know the MW of the compounds...otherwise if its just some random crap your prolly gonna have to think about it for a minute or two
 
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elz787 said:
is there an easy way to find the limiting reagent ?


I want to know why u are asking this question.
Is it because you don't know how to find limiting reagent?
if then I can help you.

If it's because you know how to find limiting reagent, but lazy, then my answer is no, there is no way you can find it. Unless you wanna take 50% chance and choose one.

Another problem is, even if there is a way to find limiting reagent by eyeballing, they won't just ask you find limiting reagent. that's not only too simple to be on DAT test, but also they can't give u 5 options that has 1 correct answer. So i believe they will most likely ask you how many g or mol of product is made by the amount of limiting agent, or how many g or mol are left even after reaction, because one is limiting and the other one is exessive, which means it has more than limiting so there should be some amount left after reaction.
 
i was just wondering if there was another route other than dimensional analysis, since sometimes it takes a long time.
 
elz787 said:
i was just wondering if there was another route other than dimensional analysis, since sometimes it takes a long time.

what's dimensional analysis?
 
joonkimdds said:
what's dimensional analysis?

Using conversion factors to figure something out.

Example: (too lazy to think of a limiting reagent dimensional analysis example :oops:)
36 g of H2O is how many moles of H2O?

36 g H2O * (1 mol H2O/18 g H2O) = 2 mol H2O

The benefit of this is that you can really tell if you're lining up your units correctly.
 
Finding the limiting reagent is pretty easy. First of all, you look at the moles of the reactants and select the one with the highest number of moles with highest M.W., most likely it is the limiting reagent. Also, look at the amount of grams given. You can usually predict which one is going to be limiting if you take all the above in consideration.
 
Flipper405 said:
Using conversion factors to figure something out.

Example: (too lazy to think of a limiting reagent dimensional analysis example :oops:)
36 g of H2O is how many moles of H2O?

36 g H2O * (1 mol H2O/18 g H2O) = 2 mol H2O

The benefit of this is that you can really tell if you're lining up your units correctly.


oh that thing is called dimensional analysis? wow...i know how to do it :)
 
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