Identification and Reaction of Compound X with Aluminium:

• (a) Compound X used to join railway tracks is thermite, which is a mixture of iron(III) oxide (Fe2O3) and aluminium powder.
• (b) The reaction is a thermite reaction.
• (c) Reaction:
  • Fe2O3(s) + 2Al(s) → 2Fe(l) + Al2O3(s) + heat

Cinnabar and Extraction of Metal:

• Cinnabar is mercury sulfide (HgS), a naturally occurring ore of mercury.
• Metal is extracted from cinnabar through the process of roasting, followed by reduction with carbon or hydrogen.
• During roasting, cinnabar is heated in the presence of oxygen to form mercury oxide (HgO), which is then reduced to elemental mercury (Hg) using carbon or hydrogen as reducing agents.
• Overall reaction:
  • 2HgS(s) + 3O2(g) → 2HgO(s) + 2SO2(g)
  • 2HgO(s) + C(s) → 2Hg(l) + CO2(g)

Identification of Metal A and Amphoteric Oxide B:

• Metal A used in the thermite process is iron (Fe).
• Oxide B is iron(III) oxide (Fe2O3), which is amphoteric in nature.
• Reactions of oxide B with HCl and NaOH:
  • With HCl: Fe2O3(s) + 6HCl(aq) → 2FeCl3(aq) + 3H2O(l)
  • With NaOH: Fe2O3(s) + 6NaOH(aq) → 2Na3Fe(OH)6

Identification of Non-metal A and Its Oxides B and C:

• Non-metal A is carbon (C).
• Oxide B is carbon monoxide (CO), which is toxic.
• Oxide C is carbon dioxide (CO2), which contributes to global warming.