How many milliliters of 30% nitric acid (p = 1.184 g / cm3) is needed to dissolve 1 g of copper.

Given:
ω (HNO3) = 30%
ρ solution (HNO3) = 1.184 g / cm3 = 1.184 g / ml
m (Cu) = 1 g

To find:
V solution (HNO3) -?

Decision:
1) 8HNO3 + 3Cu => 3Cu (NO3) 2 + 2NO + 4H2O;
2) n (Cu) = m (Cu) / M (Cu) = 1/64 = 0.0156 mol;
3) n (HNO3) = n (Cu) * 8/3 = 0.0156 * 8/3 = 0.0416 mol;
4) m (HNO3) = n (HNO3) * M (HNO3) = 0.0416 * 63 = 2.6208 g;
5) m solution (HNO3) = m (HNO3) * 100% / ω (HNO3) = 2.6208 * 100% / 30% = 8.736 g;
6) V solution (HNO3) = m solution (HNO3) / ρ solution (HNO3) = 8.736 / 1.184 = 7.378 ml.

Answer: The volume of the HNO3 solution is 7.378 ml.