=-calculez masa de sulfat de cupru din solutie
c=mdx100/ms
10= mdx100/22,4---------------------> md= 2,24g CuSO4
-calculez masa de precipitat format, cu masa molara M= 98g/mol
2mol..............1mol
CuSO4 + 2NaOH-----> Cu(OH)2 ↓ + Na2SO4
2x40g...............98g
2,24g...............x=......................calculeaza !!!!