Question

1) Ce concentratie molara are o solutie care contine 2g soda caustrica in 250 ml sol.
2)In 450 cm^3 sol sulfat de cupru se gasesc 16 g sulfat de cupru . Sa se calculeze concentratia molara

Answer 1

1)Msodacaustrica(NaOH) = 23 + 1 + 16= 40 g/mol

250 mL = 0.25 L

CM = (2 g/ 40 g/mol) / 0.25 = 0.2 mol/L

2) 450 cm^3 = 0.45 L
    M CuSO4 = 160 g/mmol

CM = (16 g/ 160 g/mol) / 0.45 L = 0.22 mol/L