Question

se amesteca 125g piatra vanata cu 200g H2O si cu 400g solitue CuSo4, C=10%, determinati C% a soluției obținute ​

Answer 1

piatra vanata = CuSO4*5H2O

M.cristaloh. = 160+90 = 250 g/mol

250 g cristaloh.  ............. 160 g CuSO4 ..... 90 g H2O

125 g ................................. a ........................... b

=> a = 80 g CuSO4

=> b = 45 g H2O

ms = 400 g , c = 10%

stim ca c% = mdx100/ms

=> md = msxc/100 = 400x10/100 = 40 g CuSO4

=> md.final = md + a = 40 + 80 = 120 g

ms.final = ms + b + m.apa = 400 + 45 + 200 = 645 g

=> c.final = md.finalx100/ms.final = 120x100/645

=> c.final = 18,6%