Question

Am nevoie de ex 2,3,6,7 va rog!

Answer 1

Răspuns:

ms= 1kg= 1000g

c=mdx100/ms---> md= 15x1000/100g=150g

m,sare= 120g    m,apa= ms-md= 1000g-150g=850g

c,m= niu/V----> niu= 2mol/lx 1 l= 2mol

m=niuxmiu= 2molx36,5g/mol= 73gHCl

la pH=7, solutia este neutra, deoarece    [H3O⁺]=[OH⁻]

adaugand acid,solutia devine acida, deoarece creste conc.H3O⁺]

c,n= 0,0001 Eg/l

1Eg,H2SO4= miu/2 => c,m=0,5mol/l H2SO4

1molH2SO4/l........2mol H⁺/l

0,00005mol/l..........x=

x= 0,0001mo/l H⁺

pH= -log[H⁺]= 4

Explicație: