Question

datele sunt cele de mai jos, ingrosate
va rog mult sa ma ajutati

Answer 1

Răspuns:

utilizez formula  C= mdx100/ms

sol.A( sol.1)

md1=300g

m,s1= 1500g

c1= 300x100/1500= 20%

sol.B

m,impur= 60g

md2= m,pur= 60x85/100g=51g

m,apa= 300g

ms2=md2+m,apa= 351

c2= 51x100/351=14,5%

sol.C\

ms1= 280g

ms2=120g

c3= md3x100/ms3= (md1+md2)x100/ (ms1+ms2)

md1= c1xms1/100=20x280/100g=56g

md2= 14,5x120/100g=17,4g

md3= 73,4g

ms3=400g

c3= 73,4x100/400=18.35%

c,m= niu/V,l

niu=md3/miu= 73,4/74,5mol= 0,985

V=ms3/ro= 400/1,1ml=363,6ml=0,3636 l

c,m= 0,985mol/0,3636 l=2,7 mol/l  

verifica, te rog, calculele !

Explicație: