-calculez masa si moli de AgNO3 din solutie
c=mdx100/ms
10=mdx100/68----> md= 6,8g
n=m/M-----> n= 6,8g/170g/mol= 0,04molAgN03
-deduc moli NaCl
1mol ...1mol
AgNO3 + NaCl---> AgCl + NaNO3
0,04mol.....x= 0,04molNaCl
-deduc moli HCll si NaOH si masa HCl
1mol..... 1mol.................1mol
HCl + NaOH ----> NaCl + H2O
x=0,04.. . y=0,04..............0,04mol
m,HCl= 0,04molx36,5g/mol=1,46g
n,NaOH=0,04mol
-rezulta masa si moli de acid sulfuric :
m,H2SO4= 4,4g-1,46g= 2,96g
nH2SO4= 2,96g/98g/mol= 0,03mol
- deduc moli NaOH din reactia
2mol.................1mol
2NaOH + H2SO4----> Na2SO4 + 2H2O
x=0,06mol......0,03mol
total moli NaOH=0,04+0,06=> 1MOL
m=md= 1molx40g/mol=40g
-calculez masa solutiei NaOH 20%
c=mdx100/ms
20= 40x100/ms............................
