When vapours of ethyl alcohol are passed over Al₂O₃ at 533 K, it forms

$2{\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{OH}\underset{523 \mathrm{K}}{\overset{{\mathrm{Al}}_2{\mathrm{O}}_3}{\to }}\underset{\mathrm{ethoxy} \mathrm{ethane}}{{\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{O}-{\mathrm{CH}}_2-{\mathrm{CH}}_3}$

When vapors of ethyl alcohol are passed over Al₂O₃ at 523 K, it forms ethoxy ethane.