Answer:
3 g
Explanation:
Concentration of copper nitrate needed = 30 g/dm³
Volume of water = 100 cm³ = 0·1 dm³
( ∵ 1 dm³ = 1000 cm³)
Let the mass of copper nitrate that should be added to 100 cm³ water be m g
m ÷ 0·1 = 30
∴ m = 3 g
∴ Mass of copper nitrate that should be added to 100 cm³ of water = 3 g