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今年江苏化学预选试题中,有这样一道题:“下列常用仪器中,用于测量液体体积的是 A.试管 B.胶头滴管 C.滴定管 D.烧杯”(标准答案为C。) 我认为题中“测量”一词用得不确切。因为“测量液体体积”是指通过量具来确定一种未知体积的液体的体积,液体在量具内所占的体积必须能通过具体刻度反映出来。胶头滴管没有具体刻度,烧杯、试管表示的容积很不准确,这三种仪器都不能用作精确测量液体的体积。滴定管只有中间一段有刻度,在0刻度以上和终刻度以下都无刻度,刻度线以外的部分是不能用作测量液体体积的。如向50ml
This year’s Jiangsu Chemical Preselection Question has such a question: “The following commonly used instruments used to measure the volume of liquid is A. test tube B. plastic dropper C. burette D. beaker” (standard answer is C.) I think The word “measurement” in the title is not exactly used. Because “measurement volume of liquid” refers to the volume of an unknown volume of liquid determined by a gage, the volume of liquid in the gage must be reflected by a specific scale. There is no specific scale for the plastic dropper, and the volume indicated by the beaker or test tube is inaccurate. None of these three instruments can be used to accurately measure the volume of the liquid. The burette is scaled only in the middle section. There are no scales above the 0 scale and below the final scale. Parts outside the scale cannot be used to measure the liquid volume. As to 50ml