question_answer 96)

  A tetravalent element forms monoxide and dioxide with oxygen. When air is passed over heated element (1273K), producer gas is obtained. Monoxide of the element is a powerful reducing agent and reduces ferric oxide to iron. Identify the element and write formulae of its monoxide and dioxide. Write chemical equations for the formation of producer gas and reduction of ferric oxide with the monoxide.

Answer:

  The element is carbon. It forms two oxides: (a) CO and (b)\[C{{O}_{2}}\]. When air is passed over heated carbon at 1273 K, producer gas is formed. \[2C+\underset{Air}{\mathop{({{O}_{2}}+{{N}_{2}})}}\,\xrightarrow{2}\underbrace{CO+{{N}_{2}}}_{\Pr oducer\,gas}\] CO is a powerful reducing agent. It reduces ferric oxide into iron. \[F{{e}_{2}}{{O}_{3}}+CO\xrightarrow{{}}2FeO+C{{O}_{2}}\]                 \[FeO+CO\xrightarrow{{}}Fe+C{{O}_{2}}\]