Finding limiting reagent
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Finding limiting reagent
What is the easiest/quickest way to determine what the limiting reagent in a chemical reaction is?
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Re: Finding limiting reagent
Determine the moles of each reactant, convert both to either moles or grams product produced. Whichever produces less moles or grams of product is limiting.
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Re: Finding limiting reagent
You also need to take into account the ratio of the reactants to each other. For example, if the ratio of two reactants, CO2 and H2O, is anything besides 1:1, you need to determine how much product will be produced by each quantity of reactants, then determine which one is limiting.
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Re: Finding limiting reagent
Find how many moles of reactant you have. Then, pick a product to convert said moles into to see how many moles of the product are produced by each reactant. Whichever produces the least product is the limiting reactant. You can also kind of cheese this process though by eyeballing molar ratios and molar masses if you are given the same mass of each reactant (in very specific contexts though).
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Re: Finding limiting reagent
I think everyone before me gave great advice but I'd also like to add that it doesn't matter which product of a reaction you use. Just make sure to be consistent. If it's easier to calculate how much product "A" is formed as opposed to how much product "B" (based on the stoichiometric ratios) then choose A. UNLESS the problem asks you to calculate a certain product then do that one instead, but if the question solely asks for the limiting reactant, then use the product that's most easiest to calculate.
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Re: Finding limiting reagent
Can someone clarify on how to do the mole to mole ratio in order to find the limiting reagent?
Re: Finding limiting reagent
The process that helps me the most with the mole to mole ratio is this. 1. Convert grams of reactant to moles of the reactant using molar mass. 2. Convert the moles of the reactant to moles of the reactant using the stoichiometric coefficients given in the balanced chemical equation (for example, if you had 1.4 moles of H2O and the coefficient of H2O in the equation is 2, then you would divide 1.4 moles by 2 in order to get the moles of the reaction in terms of H2O) - you would do this which each reactant (if given initial amounts of both reactants) in order to find out which one is the limiting reactant.
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