When a sample of NO₂ is placed in a container, this equilibrium is rapidly established.
$2{\mathrm{NO}}_2\left(\mathrm{g}\right)\rightleftharpoons {\mathrm{N}}_2{\mathrm{O}}_4\left(\mathrm{g}\right)$
If this equilibrium mixture is a darker colour at high temperatures and at low pressure, which of these statements about the reaction is true?

The reaction is exothermic and N₂O₄ is darker in colour than NO₂

The reaction is endothermic and NO₂ is darker in colour than N₂O₄

The reaction is exothermic and NO₂ is darker in colour than N₂O₄

The reaction is endothermic and N₂O₄ is darker in colour than NO₂