Ammonia formation via Haber process precursors

Steps:

• Ammonia (NH3) forms from N2 and H2 in the Haber-Bosch process.
• N2 is sourced directly from air, identifying substance 2 as nitrogen.
• H2 derives from hydrocarbons; long-chain alkanes undergo cracking to yield shorter chains for steam reforming into H2.
• Process X must be cracking, as fractional distillation only separates fractions without bond-breaking.

Why A is correct:

• Cracking thermally or catalytically breaks C-C bonds in long-chain alkanes (e.g., C16H34 → C8H18 + C8H16), providing alkenes and alkanes for H2 production via CH4 + H2O → CO + 3H2, then combined with N2.

Why the others are wrong:

• B: Fractional distillation separates crude oil by boiling points but does not generate H2 precursors; oxygen is irrelevant for ammonia.
• C: Cracking starts with alkanes, not alkenes, which are products, not inputs.
• D: Fractional distillation is incorrect for bond cleavage; oxygen is not used in ammonia synthesis.

Final answer: A