试题与答案

铁是人体必需的微量元素,它是血红蛋白的成分,能帮助氧气的运输.所以,缺少铁元素,

题型:填空题

题目:

铁是人体必需的微量元素,它是血红蛋白的成分,能帮助氧气的运输.所以,缺少铁元素,人体易患的疾病为______,医学上经常用硫酸亚铁糖衣片给这种病人补铁.小明对这种糖衣片进行探究活动.

【提出问题】:这种糖衣片中是否含有FeSO4,若有,含量是多少?

【查阅资料】:①亚铁离子遇具有氧化性的物质时易被氧化.如氢氧化亚铁为白色沉淀,在空气中会迅速被氧化成红褐色的氢氧化铁沉淀,这是氢氧化亚铁的特性.

②亚铁盐溶于水时,极易产生少量氢氧化亚铁沉淀(溶液浑浊).

【实验验证】:(1)鉴定硫酸亚铁成分时需先加水溶解并加几滴盐酸.你认为加几滴盐酸的作用______.能否用稀硫酸代替?______(填“能”或“不能”).

(2)检验亚铁盐可用的试剂是______,现象为______.

检验SO42-,确定硫酸盐.

(3)含量测定:

①取十粒糖衣片,称其质量为5g,溶于20g水中;

②向所配溶液中滴加BaCl2溶液至略过量;证明BaCl2溶液过量的操作:静置,向上层清液中滴加______溶液,若现象为______,则溶液已过量.

③过滤、洗涤、干燥;

④称量得,沉淀质量为4.66g.

⑤含量计算:该糖衣片中硫酸亚铁的质量分数为______.

【总结反思】:对硫酸亚铁来说,药片的糖衣可以起______的作用.

答案:

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