<img class="kfformula" src="20200629/1593408044375429.png" data-latex="在{N}_{2}+{3H}_{2}-{2NH}_{3}反应中" width="193" height="32"/>，使用催化剂的理由是（）。

【单选题】【消耗次数：1】

① 没有催化剂该反应不能发生

② 使化学反应速率增大

③ 使平衡向正方向移动

④ 抑制逆反应的发生

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