What happens when water vapour is passed over red hot iron?

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Q: 93 (CDS-I/2004)
What happens when water vapour is passed over red hot iron?

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,8,22,4,12,8,6

keywords: 

{'water vapour': [0, 0, 1, 2], 'red hot iron': [0, 0, 1, 0], 'hydrogen': [0, 0, 1, 3], 'fe2os': [0, 0, 1, 0], 'fe203': [0, 0, 1, 2], 'oxygen': [3, 0, 1, 0], 'fe304': [0, 0, 1, 0]}

When water vapor is passed over red hot iron, a chemical reaction takes place. Iron (Fe) reacts with water (H2O) to produce hydrogen gas (H2) and iron(II,III) oxide (Fe3O4), also known as magnetite.

Option 1: Hydrogen and Fe2Os are produced - Fe2Os does not exist; this is an incorrect option.

Option 2: Hydrogen and Fe203 are produced - Fe203 is iron(III) oxide, also know as rust. However, in this reaction, Fe3O4 is produced, not Fe203. This option is incorrect.

Option 3: Hydrogen and Fe304 are produced - Fe304 is iron(II,III) oxide, also known as magnetite. This is the correct option.

Option 4: Oxygen and Fe(OH)2 are produced - Fe(OH)2 is iron(II) hydroxide. This reaction does not occur when water vapor is passed over red hot iron. This option is incorrect.

In conclusion, when water vapor is passed over red hot iron, the correct answer is option 3, where hydrogen gas and iron(II,III) oxide (Fe3O4) are produced.