MCQ Detailed View

When a hydrocarbon reacts with steam in the presence of a nickel (Ni) catalyst at high temperature (around 900 °C), the main products are carbon monoxide (CO) and hydrogen gas (H₂). This gaseous mixture is known as water gas or synthesis gas (syngas). The general reaction can be written as:

CnH2n+2+nH2O →Ni,900°C nCO+(2n+1)H2C_nH_{2n+2} + nH₂O \ \xrightarrow{Ni, 900°C} \ nCO + (2n+1)H₂CnH2n+2+nH2O Ni,900°C nCO+(2n+1)H2

This process is also called steam reforming of hydrocarbons. It is an important industrial method for producing hydrogen and synthesis gas, which are key raw materials in the chemical industry.

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  Carbon monoxide (CO) formed in the reaction is later used in the Fischer–Tropsch process and other industrial syntheses.

  
  


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  Hydrogen (H₂) is vital for ammonia production (Haber process), refining petroleum, and as a clean fuel.

  
  

The other options given in the question do not fit:

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  CO₂ + O₂ is not produced in steam reforming.

  
  


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  CO₃ + H₂O is not a valid product.

  
  


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  Laughing gas (N₂O) is unrelated to hydrocarbons with steam.

  
  

Nickel acts as an effective catalyst to break down strong C–H bonds in hydrocarbons, allowing steam to oxidize the carbon into CO while releasing hydrogen. The high temperature of 900 °C ensures that the reaction proceeds efficiently.

Therefore, the reaction of steam with a hydrocarbon in the presence of Ni catalyst at 900 °C gives CO + H₂ (water gas) as the main product. This process is a fundamental industrial reaction in inorganic chemistry and chemical engineering.