Question

care este concentratia procentuala a unei solutii de zahar obtinuta prin adaugarea a 300grame apa peste 500grame solutie de concentratie 25%

Answer 1

• ms=500g
c=25%
c=(md*100):ms=> md=(c*ms):100=> md=125g
Md niciodata nu se modifica, doar ms se modifica.
• ms'=md+m(apa)=> ms'=300+125=> ms'=325g
• c'=(md*100):ms'=> c'=(125*100):325=> c'=12500:325=> c'=500:13%