某厂以工业粗盐(含Ca2+、Mg2+、SO42-等杂质)为主要原料采用“侯氏制碱法”生产纯碱和化肥NH4Cl,其工艺流程如图所示: 【查阅资料】氯化铵受热易分解:NH4Cl NH3↑+ HCl↑。回答下列问题: (1)“除杂”步骤中需加入两种试剂,按加入顺序写出化学式: ▲ 、 ▲ 。 (2)反应②的化学方程式是 ▲ 。 (3)“系列操作”包括 ▲ 、 ▲ 、过滤。 (4)不用其它试剂,检查NH4Cl产品是否纯净的实验方案是(请补—Who was in this room when Dr. Liu called? —________ you ________ I was here just now. We were both playing basketball on the playground.
[ ]A. Both… and B. Either… orC. Neither…norD. Whether… or