Question

Doar 14 , 15
Puteti scrie pe o foaie sau ceva sa fie mai usor
Va rog

Answer 1

14.

preparati o solutie de saramura de concentratie c% = 20% folosind 400 mL apa.

V.apa = 400 mL = 400 g

c% = 20% = mdx100/ms

stim ca ms = md+m.apa

=> 20 = mdx100/(md+400)

=> md = 8000/80 = 100 g sare de bucatarie

facem proba

md = 100 g, ms = 100+400 = 500 g

=> c% = 100x100/500 = 20%

15.

preparati o solutie de sirop de concentratie c% = 25% folosind 1200 g apa.

m.apa = 1200 g

c% = 25% = mdx100/ms

stim ca ms = md+m.apa

=> 25 = mdx100/(md+1200)

=> md = 30000/75 = 400 g sare de bucatarie

facem proba

md = 400 g, ms = 400+1200 = 1600 g

=> c% = 400x100/1600 = 25%