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实验室用NaOH固体配制250mL 1.25mol/L的NaOH溶液，填空并请回答下列问题： （1）配制250mL 1.25mol/L的NaOH溶液，取NaOH的质量 g （2）配制时，其正确的操作顺序是（字母表示，每个字母只能用一次） ； A、用30mL水洗涤烧杯2-3次，洗涤液均注入容量瓶，振荡 B、用天平准确称取所需的NaOH的质量，加入少量水（约30mL），用玻璃棒慢慢搅动，使其充分溶解 C、将已冷却的NaOH溶液沿玻璃棒注入250mL的容量瓶中 D、将容量瓶盖紧，颠倒摇匀 E、改用胶头滴管加水，使溶液凹面恰好与刻度相切 F、继续往容量瓶内小心加水，直到液面接近刻度1-2cm处 （3）溶液注入容量瓶前需恢复到室温，这是因为 ； （4）下列配制的溶液浓度偏低的是 ； A、称量NaOH时，砝码错放在（已移动游码） B、向容量瓶中转移溶液时不慎有液滴洒在容量瓶外面 C、加蒸馏水时不慎超过了刻度线 D、俯视刻度线 E、配制前，容量瓶中有少量蒸馏水 （5）若实验过程中出现如下情况如何处理？加蒸馏水时不慎超过了刻度线 ．
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