密度计检定中为什么要使用规定的检定液进行检定？
参考答案：
这主要是因为不同液体的毛细常数不同将使液体在密度计干管上爬升不同的高度，给密度计的读数带来误差，即使两种液体密度相同，也可能有极为不同的毛细常数，所以必须用规定的液体掺配成密度和毛细常数都符合要求的溶液进行检定。只有用统一的检定液，密度量值传递时才能使毛细常数的影响小到可以忽略的程度。
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