问题 问答题

2005年4月12日凌晨,一辆停放在箭盘山加油站内载有16t浓盐酸的罐体车底部突然发出泄漏,并冒出浓浓白雾,石灰石地面冒出许多气泡.消防队员赶赴现场,用水枪对泄漏出来的盐酸进行稀释,并采取其他措施.请根据初中所学知识回答:

①依据以上叙述写出浓盐酸的一点物理性质,并用化学方程式表示盐酸的一点化学性质.

②罐体车不能直接用铁罐装盐酸.请解释原因并写出反应的化学方程式.

③稀释后的盐酸如果直接流进附近的农田,会对农作物生长不利.请解释原因,并对此提出一条合理化建议.

答案

①根据题给信息内容,可得出浓盐酸的一点物理性质:浓盐酸具有挥发性(或浓盐酸可溶于水);能与石灰石发生反应的化学性质用化学方程式可表示为:CaCO3+2HCl═CaCl2+CO2↑+H2O;

②因为铁能与盐酸发生如下反应:Fe+2HCl═FeCl2+H2↑,从而使铁罐被腐蚀,故罐体车不能直接用铁罐装盐酸.

③农作物一般适合在中性或接近中性的土壤中生长,稀释后的盐酸流到农田中使其酸性增加,对农作物生长不利,因此可以用熟石灰粉末中和流入农田的盐酸.

所以本题答案为:①浓盐酸具有挥发性,CaCO3+2HCl═CaCl2+CO2↑+H2O;

②铁能与盐酸反应生成易溶于水的氯化亚铁而导致铁罐被腐蚀,Fe+2HCl═FeCl2+H2↑;

③盐酸能使土壤酸化,可以加入氢氧化钙改良.

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