Question

Va rog repede ex 4 si 5 cu rezolvarea completa plsss

Answer 1

Răspuns:

Explicație:

4.

md = 50g

c = 20%

ρ = 1,09 g/mL

Vs = ?

--------------------

c = md × 100 : ms => ms = md × 100 : c

ms = 50 × 100 : 20 = 250g

ρ = ms : Vs => Vs = ms : ρ

Vs = 250 : 1,09 = 229,35 mL

5.

ms₁ = 250g

c₁ = 20%

md = 50g

m(apă evaporată) = 100g

c₂ = ?

--------------------

md₁ = md₂ = md = 50g

ms₂ = ms₁ - 100g

ms₂ = 250g - 100g

ms₂ = 150g

c₂ = md × 100 : ms₂

c₂ = 50 × 100 : 150 = 33,33%

-Mihai