Question

Ile cm3 , 80cio% roztworu kwasu siarkowego6 (d=1,4g/cm3) należy użyć do przygotowania 500cm3 jedno 10 molowego roztworu.

Answer 1

 

V = 500cm³ = 0,5dm³

d = 1,4g/cm³

cp = 80%

M H₂SO₄ - 98g/mol

cm = 10mol/dm³

cp = 80%

 

cm = n/V => n = cm x V

 

n = 10mol/dm³ x 0,5dm³ = 5moli

 

n = m/M => m = nM

 

m = 5moli x 98g/mol = 490g

 

ms = 490g

cp = ms/mr x 100% => mr = ms x 100%/cp

 

mr = 490g x 100%/80% = 612,5g

 

V = m/d

 

V = 612,5g/1,4g/cm³ = 437,5cm³

 

 

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Pozdrawiam :)