Answer:
600 moles of (NH₄)₂SO₄ are required
Explanation:
If concentration is in m, this means molality.
Molality is reffered to the moles of solute, in 1 kg of solvent.
Volume of solvent = 200L
If we use density, we assume that solvent is water so:
1 g/mL = solvent mass / solvent volume
200L . 1000 = 2x10⁵ mL
1g/mL = solvent mass / 2x10⁵ mL
200000 g = solvent mass
In 1kg of water we have 3 m
In 200 kg of water we have (200 . 3)/1 = 600 moles