K2O+N2O5=2KNO3 djn nfr вот так
дано
m техн (C2H4) = 92 g
W( пр.C2H4) = 20%
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m(C2H5OH)-?
m чист.(C2H4) = 92 - (92 * 20% / 100%) = 73.6 g
C2H4 + H2O-->C2H5OH
M(C2H4) = 28 g/mol
n(C2H4) = m/M = 73.6 / 28 = 2.63 mol
n(C2H4) = n(C2H5OH) = 2.63 mol
M(C2H5OH) = 46 g/mol
m(C2H5OH) = n*M = 2.63 * 46 = 120.98 g
ответ 120.98 г
3 моль
nh3 + hcl = nh4cl
N(nh3)=N(hcl) => N(nh4cl) = 3 моль
Дано:
m(H₂O) = 150г
m(H₃PO₄) = 50г
Найти:
w(H₃PO₄)
Решение:
w(H₃PO₄) =
![\frac{m(H_3 PO_4 )}{m(p-pa)}](https://tex.z-dn.net/?f=+%5Cfrac%7Bm%28H_3+PO_4+%29%7D%7Bm%28p-pa%29%7D+)
m(p-pa) = 150 + 50 = 200г
w(H₃PO₄) =
![\frac{50}{200} = 0,25 * 100](https://tex.z-dn.net/?f=+%5Cfrac%7B50%7D%7B200%7D+%3D+0%2C25+%2A+100+)
% = 25%
Ответ: w(H₃PO₄) = 25%