How much acetic acid and water do you need to take to prepare 1 kg of a 2% solution?

Given:

m (solution) = 120 g,

w = 20%,

m (substances) -?

Solution :

w = m (substance): m (solution) × 100%, hence

m (substance) = (m (solution) × W): 100%.

m (substance) = (1000 × 2%): 100% = 20 g.

m (water) = m (solution) – m (substance).

m (water) = 1000 g – 20 g = 980 g.

Answer: 20 g of acid; 980 g of water must be taken to prepare the solution.