If we have 2.500g of CuCl2•2H2O and 2.200 g of Cu to make CuCl. What is the theoretical yield?
You need to confirm molar masses and all the calculations. My calculator is on the blink and I've just estimated the calculations and molar masses.
CuCl2*2H2O + Cu ==> 2CuCl + 2H2O
mols CuCl2*2H2O = grams/molar mass = 2.500/170 = 0.015
mols Cu = 2.200/63 = 0.035
How much CuCl can we get with CuCl2*2H2O? That's
0.015 mols CuCl2*2H2O x (2 mol CuCl/1 mol CuCl2*2H2O) = about 0.030
How much CuCl can we get with Cu? That's
0.035 x (2 mol CuCl/1 mol Cu) = 0.070
The limiting reagent is CuCl2*2H2O; therefore, we will get about 0.030 mols CuCl from CuCl2*2H2O. Then grams CuCl = mols CuCl x molar mass CuCl = ? and this is the theoretical yield.
To determine the theoretical yield of CuCl, you need to calculate the limiting reagent in the reaction between CuCl2•2H2O and Cu.
1. Start by calculating the moles of CuCl2•2H2O:
Given mass of CuCl2•2H2O = 2.500g
Molar mass of CuCl2•2H2O = (1 mol of Cu x 63.546 g/mol) + (2 mol of Cl x 35.453 g/mol) + (2 mol of H2O x 18.015 g/mol)
= 63.546 g/mol + 70.906 g/mol + 36.030 g/mol
= 170.482 g/mol
Moles of CuCl2•2H2O = Given mass / Molar mass
= 2.500 g / 170.482 g/mol
≈ 0.014653 mol
2. Now calculate the moles of Cu:
Given mass of Cu = 2.200 g
Molar mass of Cu = 63.546 g/mol
Moles of Cu = Given mass / Molar mass
= 2.200 g / 63.546 g/mol
≈ 0.034641 mol
3. Next, examine the balanced chemical equation to determine the stoichiometric ratio between CuCl2•2H2O and Cu:
CuCl2•2H2O(s) + 2 Cu(s) → 2 CuCl(s) + 2 H2O(g)
The stoichiometric ratio is 1:2, meaning it takes one mole of CuCl2•2H2O and two moles of Cu to produce two moles of CuCl.
4. Compare the moles of CuCl2•2H2O and Cu to find the limiting reagent:
In this case, CuCl2•2H2O is the limiting reagent because the moles of CuCl2•2H2O (0.014653 mol) are smaller than the moles of Cu (0.034641 mol).
5. Calculate the moles of CuCl produced from the limiting reagent:
Since the stoichiometric ratio is 1:2, the number of moles of CuCl produced will be half the number of moles of CuCl2•2H2O:
Moles of CuCl produced = Moles of limiting reagent x (2 moles of CuCl / 1 mole of CuCl2•2H2O)
≈ 0.014653 mol x (2 mol / 1 mol)
≈ 0.029307 mol
6. Finally, convert moles of CuCl produced to grams:
Molar mass of CuCl = (1 mol of Cu x 63.546 g/mol) + (1 mol of Cl x 35.453 g/mol)
= 63.546 g/mol + 35.453 g/mol
= 98.999 g/mol
Theoretical yield of CuCl = Moles of CuCl produced x Molar mass of CuCl
≈ 0.029307 mol x 98.999 g/mol
≈ 2.930 g
Therefore, the theoretical yield of CuCl is approximately 2.930 grams.
To determine the theoretical yield of CuCl, we need to calculate the stoichiometric ratio between CuCl2•2H2O and CuCl. The balanced chemical equation for the reaction is:
CuCl2•2H2O + 2Cu -> 4CuCl + 2H2O
From the equation, we can see that for every 1 mol of CuCl2•2H2O, we can produce 4 mol of CuCl.
First, let's calculate the number of moles of CuCl2•2H2O:
molar mass of CuCl2•2H2O = (63.546 g/mol Cu + 35.453 g/mol Cl) * 2 + 2 * (1.008 g/mol H * 2 + 16.00 g/mol O) = 170.48 g/mol
moles of CuCl2•2H2O = mass / molar mass = 2.500 g / 170.48 g/mol = 0.014662 mol
Based on the stoichiometric ratio, we can calculate the theoretical yield of CuCl:
theoretical yield of CuCl = moles of CuCl2•2H2O * (4 mol CuCl / 1 mol CuCl2•2H2O) = 0.014662 mol * 4 = 0.058648 mol
To convert this into grams, we can use the molar mass of CuCl:
molar mass of CuCl = 63.546 g/mol + 35.453 g/mol = 99.999 g/mol (rounded to 100 g/mol)
mass of CuCl = moles of CuCl * molar mass of CuCl = 0.058648 mol * 100 g/mol = 5.8648 g
Therefore, the theoretical yield of CuCl is approximately 5.8648 grams.