Дано:
m'(p-pa H2SO4) = 200 r
ω'(H2SO4) = 40% или 0,4
m"(p-pa H2SO4) = 600 r
ω"(H2SO4) = 10% или 0,1
ω'"(H2SO4)-?
ω'"(H2SO4) = [m'*ω'+m"*ω"]/[m'+m"] = (200*0.4+600*0.1]/[200+600] =
=140/800 = 0.175 или 17,5%
Ответ: 17,5%
N(CH3COONa)=6.8/82=0.07
n(BrCH2CH3)=11/109=0.1
82г 74г
CH3COONa+BrCH2CH3=CH3COOCH3+NaBr
6.8г x=6,14г
m(CH3COOCH3)=6.14*0.9=5.5г
Zn + H2SO4 = ZnSO4 + H2
7*0.93=6.51
6.51/64=0.1
0.1/1=x/1
x=0.1
0.1*22.4=2.24 л
10 , т.к. 1s22s22p6 -> то есть 10