Q: Ethanol is converted into ethoxy ethane,

• 1
  by heating excess of ethanol with conc. H2SO4 at 140°C
• 2
  by treating with conc. H2SO4 at room temperature
• 3
  by treating with conc. H2SO4 at 273 K
• 4
  by heating Ethanol with excess of conc. H2SO4 at 443 K