1. The reactants in the chemical reaction were carefully measured before being combined.
化学反应中的反应物在混合之前被精确地测量。

2. The reactants must be mixed in the correct proportions for the reaction to occur.
反应物必须按正确的比例混合才能发生反应。

3. The reactants were heated to a high temperature to speed up the reaction.
反应物被加热到高温以加快反应速度。

4. It is important to know the properties of the reactants before conducting any experiments.
在进行任何实验之前了解反应物的性质是很重要的。

5. The reactants reacted quickly and produced a gas as a byproduct.
反应物迅速反应并产生了气体作为副产物。

6. The reactants were mixed together in a beaker and stirred gently to start the reaction.
反应物被混合在烧杯中，并轻轻搅拌以开始反应。