Consider the following reaction:
$N_{2}O_{4(g)} \rightleftharpoons 2NO_{2(g)} ; \Delta H^{0} = +58 \ kJ$
For each of the following cases $(a, b)$,determine the direction in which the equilibrium shifts:
$(a)$ Temperature is decreased
$(b)$ Pressure is increased by adding $N_{2}$ at constant $T$ and constant $V$

• A
  $a$. Towards reactant,$b$. No change
• B
  $a$. Towards product,$b$. Towards reactant
• C
  $a$. Towards product,$b$. No change
• D
  $a$. Towards reactant,$b$. Towards product