NaCl -> Na + Cl2
2NaCl -> 2Na + Cl2
a) masa impura = 200 kg
p = 80%
p = (mp/mip)*100
80 = (mp/200)*100
80 = mp/2
mp = 160g
mimp = mp + mimpuritati
200 = 160 + mimpuritati
mimpuritati = 40g
b) mNa = (160*2)/2
mNa = 160g
nCl = m/M
nCl = 160/35,5
nCl = 4,507 moli Cl
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