Question

Solubilitatea NH4Cl in apa la 0 grade Celsius este 29.4g, iar la 50 grade Celsius este de 50.4g. Sa se calculeze cantitatea de NH4Cl care trebuie adaugata la 500 g solutie saturata la 0 grade Celsius, pentru ca solutia sa devina saturata la 50 grade Celsius.

Answer 1

0°C : 100g H2O...............29,4 g NH4Cl .............129,4 g solutie
                                           x= 113,6g.....................500g
50°C                                    (113,6 +m)...................(500+m)
                                                  S........................(100+S)
                                                  50,4.g.......................150,4g
150,4(113,6 + m) = 50,4(500+m)
17085 + 150,4m = 25200 + 50,4m
100m = 8115    m = 81,15 g