copper(1) chloride reacts with hydrogen sulfide. if 9.90 grams of copper(1) chloride and 10.2 grams of hydrogen sulfide are reacted together, what is the limiting reactant?
I work these LR problems the long way.
CuCl + H2S --> Cu2S + 2HCl
mols CuCl = grams/molar mass
mols H2S = grams/molar mass
Using the coefficients in the balanced equation, convert mols CuCl to mols Cu2S.
Do the same for mols H2S to mols Cu2S.
It is likely that the values will not be the same for mols Cu2S which means one of them is not right. The correct answer in LR problems is ALWAYS the smaller value and the reagent producing that value is the LR.
How many grams of chlorine will be needed to react completely with 10g of sodium to prod0ce sodhum chloride?
To determine the limiting reactant, we need to compare the amount of each reactant to their respective stoichiometric coefficients in the balanced equation.
The balanced equation for the reaction between copper(I) chloride (CuCl) and hydrogen sulfide (H2S) is as follows:
2 CuCl + H2S -> Cu2S + 2 HCl
From the equation, we can see that 2 moles of CuCl react with 1 mole of H2S to form 1 mole of Cu2S.
First, let's calculate the number of moles for each reactant.
Molar mass of CuCl:
Cu = 63.55 g/mol
Cl = 35.45 g/mol
Molar mass of CuCl = 63.55 + 35.45 = 99.0 g/mol
Number of moles of CuCl = mass / molar mass
Number of moles of CuCl = 9.90 g / 99.0 g/mol
Number of moles of CuCl = 0.10 mol
Molar mass of H2S:
H = 1.01 g/mol
S = 32.06 g/mol
Molar mass of H2S = (2 x 1.01) + 32.06 = 34.08 g/mol
Number of moles of H2S = mass / molar mass
Number of moles of H2S = 10.2 g / 34.08 g/mol
Number of moles of H2S = 0.30 mol
Now, let's compare the ratio of moles of CuCl to H2S in the balanced equation:
CuCl:H2S = 2:1
From the calculations, we have 0.10 moles of CuCl and 0.30 moles of H2S. As the ratio is 2:1, we can see that the moles of CuCl are limited by the stoichiometry of the reaction. Therefore, CuCl is the limiting reactant in this case.
To determine the limiting reactant in a chemical reaction, you need to compare the number of moles of each reactant and their stoichiometric ratio in the balanced chemical equation.
First, let's write the balanced equation for the reaction between copper(I) chloride (CuCl) and hydrogen sulfide (H2S):
CuCl + H2S → CuS + HCl
The molar mass of CuCl is approximately 98.996 g/mol (63.55 g/mol for copper and 35.45 g/mol for chlorine). To calculate the number of moles of CuCl, divide its mass by its molar mass:
moles of CuCl = mass of CuCl / molar mass of CuCl
= 9.90 g / 98.996 g/mol
≈ 0.100 mol
The molar mass of H2S is approximately 34.082 g/mol (2.015 g/mol for hydrogen and 32.067 g/mol for sulfur). Similarly, calculate the number of moles of H2S:
moles of H2S = mass of H2S / molar mass of H2S
= 10.2 g / 34.082 g/mol
≈ 0.299 mol
Next, compare the moles of each reactant to their stoichiometric ratio in the balanced equation. From the equation, we see that one mole of CuCl reacts with one mole of H2S. Therefore, the stoichiometric ratio of CuCl to H2S is 1:1.
Comparing the moles, we have 0.100 mol of CuCl and 0.299 mol of H2S. Since the moles of CuCl are lower than the moles of H2S, the limiting reactant is CuCl. It will be entirely consumed in the reaction, while some H2S will be left unreacted.
So, the limiting reactant is copper(I) chloride (CuCl).