（1）人工降雨是缓解干旱的有效措施；（2）为预防甲状腺肿大，在

问题选择题

（1）人工降雨是缓解干旱的有效措施；（2）为预防甲状腺肿大，在食用盐中加入碘酸钾（KIO₃）；（3）医疗上用硫酸钡作“钡餐”；（4）石头纸（Rich Mineral Paper RMP）也叫石科纸，就是用磨成粉末的石头为主要原料，加上15%的聚乙烯和5%胶合剂做成的。2010年两会期间，政协委员们领到的会议通知、日程表、便签纸等都是以碳酸钙为主要原料的低碳“石头纸”。下列说法正确的是（）

A．AgI和干冰都可用于人工降雨

B．用米汤检验含碘食盐中是否含有碘元素

C．硫酸钡用作“钡餐”是因为Ba²⁺无毒

D．“石头纸”能耐强酸与强碱的腐蚀

答案

答案：A

A对都可以用于人工降雨，但原理不同，干冰，固态CO2，主要起到降温的作用，使云层温度下降，水蒸气凝结成液体而降雨。AgI，其晶体结构与冰相似，所以撒入过饱和云层后，成为凝结核，便于水汽的凝结，而形成大颗粒的雨滴落下。

B 错含碘食盐中含有KIO₃不是碘单质，不能用米汤（淀粉）检验

C错硫酸钡不溶于酸，人体服用后Ba²⁺浓度很小，构不成对人体的伤害

D错，石头纸中含有碳酸钙，能与酸反应，所以不耐强酸

完形填空。
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