You need to make 4200 mL of 0.450 M CuSO4. How many grams of CuSO4 do you need?

How many moles do you need? That is M x L = mols = 0.450 x 4.2L = ?

Then mols = grams/molar mass.

302.4 grams

I get 0.450M x 4.2L x 159.61 = 301.66 = 302g to three significant figures

To find the number of grams of CuSO4 you need, we can use the formula:

Number of moles = Concentration (M) × Volume (L)

First, convert the volume from milliliters (mL) to liters (L):

4200 mL ÷ 1000 = 4.2 L

Now, rearrange the formula to solve for moles:

Number of moles = Concentration (M) × Volume (L)

Next, plug in the given concentration and volume:

Number of moles = 0.450 M × 4.2 L

Calculate the number of moles:

Number of moles = 1.89 moles (rounded to two decimal places)

Finally, since the molar mass of CuSO4 is approximately 159.61 g/mol, multiply the number of moles by the molar mass to get the grams of CuSO4:

Grams = Number of moles × Molar mass

Grams = 1.89 moles × 159.61 g/mol

Grams = 301.57 grams (rounded to two decimal places)

Therefore, you will need approximately 301.57 grams of CuSO4 to make 4200 mL of a 0.450 M solution.