Question

determinati masa de soda caustica 5%(NaOH)care se poate neutraliza cu 20 g acid clorhidric(HCl) de concentratie 18,25%

Answer 1

-calculez masa de acid din solutie

c/100= md/ms---> 18,25/100= md/20---> md=3,65gHCl

-calculez masa de NaOH care este neutralizata de acidul obtinut:
1mol.....1mol
NaOH  + HCl------.> NaCL+ H2O
40g.........36,5g
x..............3,65g
x=4gNaOH= > masa dizolvata,md

-calculez masa solutiei de soda ce contine md
5/100= 4/ms---------------------> calculeaza ms!!!!!