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Odpowiedź :

Zad.1

I mr = 120g

Cp = 24%

ms = 24%*120g /:100% = 28,8g

II mr = 120g + 40g = 160g

ms = 28,8g

Cp = 28,8g/:160g *100% = 18%

Zad.2

V = 8dm3

ms = 312 g

M(Na2S) = (23*2 + 32)g/mol = 78g/mol

n = 312g/:78g/mol = 4mole

Cm = 4mole/:8dm3 = 0,5 mol/dm3