How many grams of salt and water do you need to take to prepare 70 g of an 8% solution

Given:

m (solution) = 70 g

ω (solution) = 8%

To find:

m (water) -?

m (salt) -?

Decision:

1. Find the mass of salt in solution by the formula:

m (salt) = (ω (solution) * m (solution)) / 100% = (8% * 70 g) / 100% = 5.6 g

2. Since the solution consists of water and salt, then

m (water) = m (solution) – m (salt) = 70 g – 5.6 g = 64.4 g

Answer: To prepare 70 g of an 8% solution, 5.6 g of salt and 64.6 g of water are needed.