Calculate the mass of the solid you must measure out to prepare 100 mL of 0.025 M CuSO4.
Note that this salt is a hydrate, so its formula is CuSO4⋅5H2O. You must include the waters of hydration when calculating the formula weights.
Would the following set-up yield the correct answer?
(100 mL CuSO4⋅5H2O) x (1 L CuSO4⋅5H2O / 1000 mL CuSO4⋅5H2O) x (0.025 mol CuSO4⋅5H2O / 1 L CuSO4⋅5H2O) x (249.7 g CuSO4⋅5H2O / 1 mol CuSO4⋅5H2O)
= 0.624 g CuSO4⋅5H2O
Any feedback is appreciated. Thanks!
CuSO4.5H2O
RMM=249.68
For 1000 ml of 1M need 249.68g
For 100 ml of 1 M need 24.968 g
For 100 ml of 0.025 M need 24.968 x 0.025 = 0.0624 g
Yes, agreed.
How many grams of S are needed to produce 10g of CuS?
The set-up you provided is indeed correct for calculating the mass of CuSO4⋅5H2O needed to prepare 100 mL of 0.025 M solution.
Let's break down the set-up step by step:
(100 mL CuSO4⋅5H2O)
Here, you start with the volume of CuSO4⋅5H2O needed, which is 100 mL.
x (1 L CuSO4⋅5H2O / 1000 mL CuSO4⋅5H2O)
To convert from milliliters (mL) to liters (L), you multiply by the conversion factor 1 L / 1000 mL.
x (0.025 mol CuSO4⋅5H2O / 1 L CuSO4⋅5H2O)
Next, you multiply by the molarity (0.025 M) of the CuSO4⋅5H2O solution, which gives you the number of moles of CuSO4⋅5H2O.
x (249.7 g CuSO4⋅5H2O / 1 mol CuSO4⋅5H2O)
Finally, you multiply by the molar mass of CuSO4⋅5H2O (249.7 g/mol) to convert from moles to grams.
= 0.624 g CuSO4⋅5H2O
The final result is 0.624 grams of CuSO4⋅5H2O.
Your set-up is correct, and the calculation is accurate. Well done!
To calculate the mass of the solid needed to prepare 100 mL of 0.025 M CuSO4⋅5H2O, you need to set up a dimensional analysis. It looks like you have set up the calculation correctly.
Let's break down the steps:
Step 1: Convert the volume from mL to L.
You have correctly included this step in your calculation. The conversion factor is 1 L / 1000 mL.
Step 2: Convert the concentration from Molarity (mol/L) to moles.
You have also included this step correctly. The concentration given is 0.025 M, so the conversion factor is 0.025 mol CuSO4⋅5H2O / 1 L CuSO4⋅5H2O.
Step 3: Calculate the molar mass of CuSO4⋅5H2O (including the waters of hydration).
The molar mass of CuSO4⋅5H2O is 249.7 g/mol, as you have correctly used in your calculation.
Step 4: Multiply all the conversion factors and cancel the units.
(100 mL CuSO4⋅5H2O) x (1 L CuSO4⋅5H2O / 1000 mL CuSO4⋅5H2O) x (0.025 mol CuSO4⋅5H2O / 1 L CuSO4⋅5H2O) x (249.7 g CuSO4⋅5H2O / 1 mol CuSO4⋅5H2O) = 0.624 g CuSO4⋅5H2O
Based on your setup, it seems that you have followed the correct steps and performed the necessary calculations accurately. Therefore, your answer of 0.624 g CuSO4⋅5H2O appears to be correct.
Keep in mind that it is always a good idea to double-check your work and ensure that all calculations and conversion factors are accurate before finalizing your answer.