1) V2O5 + 6HCl = 2VOCl2 + Cl2 + 3H2O, баланс:
2V+5 +2e- = 2V+4 | 2 | 2 | 1 |
2Cl- -2e- = Cl2 | 2 | | 1 |;
2) 3Pb + 8HNO3 = 3Pb(NO3)2 + 2NO + 4H2O, баланс:
Pb -2e- = Pb+2 | 2 | 6 | 3 |
N+5 +3e- = N+2 | 3 | | 2 |.
<span>Дано:
</span>
w (C) =
80%
w (H) =
20%
D(H2) =
15
<span>Найти: CxHy
</span>
Решение:
<span>Mr (в-ва) = 15∙ 2 = 30</span>
<span>n (э) = w(э)
∙ Mr(в-ва) \Ar(э) ∙ 100%</span>
<span>n
(C) = 80% ∙ 30 \12 ∙ 100% = 2</span>
<span>n
(H) = 20% ∙ 30\1 ∙ 100% = 6</span>
<span>n
(C) : n (H) = 2:6 = CxHy = С2H6</span>
<span>ответ: С2H6
– этан</span>
2P2O5+3HCL = POCl3 + 3HPO3
CaO+NaOH = \\\
CrO3+2NaOH = Na2CrO4 + H2O (хромат натрия (II))
<span>Al2O3 + 2NaOH = 2NaAlO2 + H2O (метаалюминат натрия)
\\\ - не идет </span>