Đáp án đúng: D
20%
${{N}_{2}}\,(M\,=\,28)$
12,4 – 2 = 10,4
⇒$\frac{{{n}_{{{N}_{2}}}}}{{{n}_{{{H}_{2}}}}}\,=\,\frac{10,4}{15,6}\,=\,\frac{2}{3}$
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$\overline{M}\,=\,6,2.2\,=\,12,4$
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${{H}_{2}}\,(M\,=\,2)$
28 – 12,4 = 15,6
${{N}_{2}}$
+
$3{{H}_{2}}$
$\rightleftarrows $
$2N{{H}_{3}}$
Ban đầu
2 mol
3 mol
Phản ứng
x mol
⟵
3x
⟶
2x
Sau phản ứng
2 – x
3 – 3x
2x
$\frac{{{d}_{trc}}}{{{d}_{sau}}}\,=\,\frac{{{n}_{sau}}}{{{n}_{trc}}}\,\Rightarrow \,\frac{6,2}{6,74}\,=\,\frac{5\,-\,2x}{5}\,\Rightarrow \,x\,=\,0,2$
$\Rightarrow \,H\,=\,\frac{3.0,2}{3}=20{\scriptstyle{}^{o}\!\!\diagup\!\!{}_{o}\;}$
