Question

200 g solutie de clorura de calciu cu concentratia procentuala 10% reactioneaza cu carbonatul de sodiu. Ce produsi rezulta si in ce cantitati?

Answer 1

CaCl₂+Na₂CO₃=CaCO₃+2NaCl

ms CaCl₂=200g
c=10%
⇒md=(c*ms)/100=(10*200)/100=20g CaCl₂

Masa molara CaCl₂=40+2*35.5=111 g/mol
Masa molara CaCO₃=40+12+3*16=100 g/mol
Masa molara NaCl=23+35.5=58.5 g/mol

111g CaCl₂...................100g CaCO₃
20g CaCl₂......................x ⇒ x=(100*20)/111=18.018g CaCO₃

111g CaCl₂...................2*58.5g NaCl
20g CaCl₂.....................y ⇒ y=21.081g NaCl