What is the molarity of CuCl2 solution that completely reacts with 10.0g of zinc , if the volume of the solution is 360mls?
Zn(s) + CuCl2(aq) �¨ ZnCl2(aq) + Cu(s)
A. 0.42
B. 0.00021
C. 0.21
D. none of these
To find the molarity of the CuCl2 solution, we first need to calculate the number of moles of Zn that reacted. Then, we use the balanced chemical equation to determine the mole ratio between Zn and CuCl2. Finally, we divide the moles of CuCl2 by the volume of the solution in liters to find the molarity.
First, calculate the number of moles of Zn:
Molar mass of Zn = 65.38 g/mol
Number of moles of Zn = mass of Zn / molar mass of Zn = 10.0 g / 65.38 g/mol ≈ 0.153 moles
According to the balanced chemical equation, the mole ratio between Zn and CuCl2 is 1:1. This means that for every 1 mole of Zn, 1 mole of CuCl2 reacts.
Now, we can find the moles of CuCl2:
Number of moles of CuCl2 = number of moles of Zn = 0.153 moles
Next, convert the volume of the solution from milliliters to liters:
Volume of solution = 360 mL = 360 mL × (1 L / 1000 mL) = 0.36 L
Finally, calculate the molarity:
Molarity = moles of CuCl2 / volume of solution = 0.153 moles / 0.36 L ≈ 0.425 M
Therefore, the molarity of the CuCl2 solution is approximately 0.425 M. Since none of the answer choices match exactly, the correct answer would be D. "none of these".