Cho các phương trình hoá học sau:
$\begin{array}{l}(1)\,Fe+{{H}_{2}}O\xrightarrow{\ge {{570}^{o}}C}FeO+{{H}_{2}}\\(2)\,2Fe+3C{{l}_{2}}\xrightarrow{{{t}^{o}}}2FeC{{l}_{2}}\\(3)\,Fe+CuO\xrightarrow{{{t}^{o}}}FeO+CuO\\(4)\,2Fe{{(N{{O}_{3}})}_{2}}\xrightarrow{{{t}^{o}}}2FeO+4N{{O}_{2}}+{{O}_{2}}\\(5)\,3Fe+2{{O}_{2}}\xrightarrow{{{t}^{o}}}F{{e}_{3}}{{O}_{4}}\\(6)\,3Fe+4{{H}_{2}}O\xrightarrow{{{t}^{o}}}F{{e}_{3}}{{O}_{4}}+4{{H}_{2}}\\(7)\,2Fe+3C{{l}_{2}}\xrightarrow{{}}2FeC{{l}_{3}}\\(8)\,Fe+S\xrightarrow{{{t}^{o}}}FeS\\(9)\,3Fe+2{{O}_{2}}\xrightarrow{{{t}^{o}}}F{{e}_{2}}{{O}_{3}}\\(10)\,2Fe+3{{I}_{2}}\xrightarrow{{{t}^{o}}}2Fe{{I}_{3}}\end{array}$
Số phương trình phản ứng viết đúng là
A. 4.
B. 5.
C. 6.
D. 7.