Question

In the laboratory you are asked to make a 0.356 m potassium sulfate solution using 315 grams of water. How many grams of potassium sulfate should you add

Answer 1

15g

Step-by-step explanation:

they're asking you to make a solution which contains 0.356 mol k2so4 per 1000 gr water, but they want you to use only 315 g of water

so you need to solve

0.356 mol k2so4 ÷ 1000gr water = X ÷ 315gr water

so you need X = 0.112 moles of k2so4

that weights

0.112 moles × ((2×19)+32+(4×16)) g/mol