Calculate the mass of copper nitrate that can be obtained from 38.4 grams of copper.

1. According to the condition of the problem, we compose the equation:
3Cu + 8HNO3 (dil.) = 3Cu (NO3) 2 + 2NO + 4H2O – OBP, copper nitrate salt obtained;
2. Calculations of molecular weights by the formulas:
M (Cu) = 63.5 g / mol;
M Cu (NO3) 2 = 187.5 g / mol.
3. Determination of the amount of mol of copper, salt:
Y (Cu) = m / M = 38.4 / 63.5 = 0.6 mol;
0.6 mol (Cu) – X mol Cu (NO3) 2;
-3 mol -3 mol from here, X mol Cu (NO3) 2 = 0.6 * 3/3 = 0.6 mol.
4. Find the mass of salt:
m Cu (NO3) 2 = 0.6 * 187.5 = 112.5 g.
Answer: the mass of copper nitrate is 112.5 g.