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 = ?
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md₁ = md₂ = md = 50g
ms₂ = ms₁ - 100g
ms₂ = 250g - 100g
ms₂ = 150g
c₂ = md × 100 : ms₂
c₂ = 50 × 100 : 150 = 33,33%
-Mihai
