Question

Do 150 g 8-procentowego roztworu wodorotlenku sodu dodano 90 g wody. Oblicz stężenie procentowe otrzymanego roztworu.

Answer 1

mr₁=150g

Cp₁=8%

ms₁=?

 

Cp=ms/mr * 100%   /*mr

Cp*mr=ms*100%   /:100%

ms=Cp*mr/100%

 

ms₁=8%*150g/100%

ms₁=12g

 

ms₂=ms₁=12g

mr₂=150g+90g=240g

Cp₂=?

 

Cp=ms/mr * 100%

Cp₂=12g/240g * 100%

Cp₂=5%

Answer 2

Cp=ms/mr x 100%

0,08=ms/150

ms=12g

 

Cp=12/(150+90) x 100%

Cp=5%