which would be the limiting reagent in the reaction: 2H2(g) + O2(g) => 2H2O(g)
1. 50 molecules of H2
or
2. 50 molecules of O2
if you put 50 molecules of H2,you would need 25 of O. So, the H2 is limiting.
To determine the limiting reagent in a reaction, we need to compare the stoichiometry of the reaction with the amounts of reactants given.
1. First, let's find the moles of H2 and O2 given:
Moles of H2 = molecules of H2 / Avogadro's number
= 50 / 6.022 x 10^23
= 8.31 x 10^-23 moles
Moles of O2 = molecules of O2 / Avogadro's number
= 50 / 6.022 x 10^23
= 8.31 x 10^-23 moles
2. Next, let's compare the number of moles of each reactant with the stoichiometric ratio in the balanced equation:
From the balanced equation, we can see that 2 moles of H2 react with 1 mole of O2 to produce 2 moles of H2O.
The mole ratio of H2 to O2 is 2:1.
Since we have an equal number of moles of H2 and O2, there is no excess of either reactant. Therefore, both H2 and O2 will be completely consumed in the reaction, and neither one is considered the limiting reagent. This means that the reaction will go to completion, producing water as the product.
To determine the limiting reagent in a chemical reaction, you need to compare the stoichiometric ratios of the reactants.
In this case, the balanced chemical equation shows that the ratio of H2 to O2 is 2:1. This means that for every 2 moles of H2, you need 1 mole of O2 to react completely.
To compare the two options given:
1. 50 molecules of H2: First, convert molecules to moles by dividing by Avogadro's number (6.022 x 10^23 molecules per mole). Then, use the stoichiometric ratio to determine the number of moles of O2 needed. If the calculated amount of O2 is less than or equal to 50 moles, then H2 is the limiting reagent.
2. 50 molecules of O2: Start by converting molecules to moles using Avogadro's number. Then, using the stoichiometric ratio, calculate the number of moles of H2 needed. If the calculated amount of H2 is less than or equal to 50 moles, then O2 is the limiting reagent.
By comparing the results of both calculations, you can determine which reactant is present in less than the required amount, thus being the limiting reagent.