不知道在实验室中工作的大家有没有遇到过这种情况:
想要移取某种溶液样品,但是发现移液器好像不准确需要进行校准。我不了解大家碰到这种情况是怎么做的,但是如果正好有人和我一样要求不是特别高,又怕麻烦,不想去计量单位校准的话,不妨可以采用我下面要讲的这个方法,也就是利用电子天平来校准移液器。那么我们具体该怎么做呢?
首先,我们需要准备一个已经校准过的电子天平,然后放一个小烧杯,去皮(即去掉装物品的篮子之类的容器的重量)。再用移液器移取一定量的蒸馏水(这里的一定量的蒸馏水需要我们自己先记好是移取了多少的量),然后移入小烧杯中称重。质量除以密度,就是蒸馏水的实际的体积了。当然在我们移取蒸馏水前最好先测下水温,因为不同温度蒸馏水的密度会有些不同,具体不同温度蒸馏水的密度见下表所示。
蒸馏水在不同温度下密度 | |||||||||||
温度 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 差数X10 |
5 | 0.9999919 | 0.9999902 | 0.9999883 | 0.9999842 | 0.9999842 | 0.9999819 | 0.9999795 | 0.9999769 | 0.9999741 | 0.9999712 | 1 |
6 | 0.9999681 | 0.9999649 | 0.9999616 | 0.9999581 | 0.9999544 | 0.9999506 | 0.9999467 | 0.9999426 | 0.9999384 | 0.999934 | 1 |
7 | 0.9999295 | 0.9999248 | 0.99992 | 0.999915 | 0.9999099 | 0.9999046 | 0.9998992 | 0.9998936 | 0.9998879 | 0.9998821 | 2 |
8 | 0.9998762 | 0.9998701 | 0.9998638 | 0.9998574 | 0.9998509 | 0.9998442 | 0.9998374 | 0.9998305 | 0.9998234 | 0.9998162 | 3 |
9 | 0.9998088 | 0.9998013 | 0.9997936 | 0.9997859 | 0.999778 | 0.9997699 | 0.9997617 | 0.9997534 | 0.999745 | 0.9997364 | 5 |
10 | 0.9997277 | 0.9997189 | 0.9997099 | 0.9997008 | 0.9996915 | 0.999682 | 0.9996724 | 0.9996627 | 0.9996529 | 0.9996428 | 6 |
11 | 0.9996328 | 0.9996225 | 0.9996121 | 0.9996017 | 0.9995911 | 0.9995803 | 0.9995694 | 0.9995585 | 0.9995473 | 0.9995361 | 2 |
12 | 0.9995247 | 0.9995132 | 0.9995016 | 0.9994898 | 0.999478 | 0.999466 | 0.9994538 | 0.9994415 | 0.9994291 | 0.9994166 | 0 |
13 | 0.999404 | 0.9993913 | 0.9993784 | 0.9993655 | 0.9993524 | 0.9993391 | 0.9993258 | 0.9993123 | 0.9992987 | 0.999285 | 1 |
14 | 0.9992712 | 0.9992572 | 0.9992432 | 0.999229 | 0.9992147 | 0.9992003 | 0.9991858 | 0.9991711 | 0.9991564 | 0.9991415 | 1 |
15 | 0.9991265 | 0.9991113 | 0.9990961 | 0.9990608 | 0.9990653 | 0.9990497 | 0.999034 | 0.9990182 | 0.9990023 | 0.9989862 | 2 |
16 | 0.9989701 | 0.9989538 | 0.9989374 | 0.9989209 | 0.9989043 | 0.9988876 | 0.9988707 | 0.9988538 | 0.9988367 | 0.9988175 | 6 |
17 | 0.9988022 | 0.9987849 | 0.9987673 | 0.9987497 | 0.9987319 | 0.9987141 | 0.9986961 | 0.9986781 | 0.9986599 | 0.9986416 | 9 |
18 | 0.9986232 | 0.9986046 | 0.9985861 | 0.9985673 | 0.9985485 | 0.9985295 | 0.9985105 | 0.9984913 | 0.998472 | 0.9984326 | 14 |
19 | 0.9984331 | 0.9984136 | 0.9983938 | 0.998374 | 0.9983541 | 0.9983341 | 0.998314 | 0.9982937 | 0.9982733 | 0.9982529 | 18 |
20 | 0.9982323 | 0.9982117 | 0.9981909 | 0.9981701 | 0.998149 | 0.998128 | 0.9981068 | 0.9981695 | 0.9980641 | 0.9980426 | 22 |
21 | 0.998021 | 0.9979993 | 0.9979775 | 0.9979556 | 0.9979335 | 0.9979114 | 0.9978892 | 0.9978869 | 0.9978444 | 0.9973219 | 25 |
22 | 0.9977993 | 0.9977765 | 0.9977537 | 0.9977308 | 0.9977077 | 0.9976846 | 0.9976613 | 0.997638 | 0.9976145 | 0.9975918 | 27 |
23 | 0.9975674 | 0.9975437 | 0.9975198 | 0.9974959 | 0.9974718 | 0.9974477 | 0.9974435 | 0.9973991 | 0.9973717 | 0.9973502 | 29 |
24 | 0.9973256 | 0.9973009 | 0.997276 | 0.9972511 | 0.9972261 | 0.997201 | 0.9971758 | 0.9971505 | 0.997125 | 0.9970995 | 30 |
25 | 0.9970739 | 0.9970432 | 0.9970225 | 0.9969966 | 0.9969706 | 0.9969445 | 0.9969184 | 0.9968921 | 0.9963657 | 0.9968393 | 31 |
26 | 0.9968128 | 0.9967861 | 0.9967594 | 0.9967326 | 0.9967057 | 0.9966726 | 0.9966515 | 0.9966243 | 0.996597 | 0.9965696 | 30 |
27 | 0.9965241 | 0.9965146 | 0.9964869 | 0.9964591 | 0.9964313 | 0.9964033 | 0.9963753 | 0.9963472 | 0.996319 | 0.9962907 | 29 |
28 | 0.9962623 | 0.9962338 | 0.9962052 | 0.9961766 | 0.9961478 | 0.996119 | 0.9961901 | 0.996061 | 0.9960319 | 0.9960027 | 28 |
29 | 0.9959735 | 0.995944 | 0.9959146 | 0.995885 | 0.9958554 | 0.9950257 | 0.9957958 | 0.9957659 | 0.9957359 | 0.9957059 | 25 |
30 | 0.9956756 | 0.9956454 | 0.9956151 | 0.9955846 | 0.9955541 | 0.9955235 | 0.9954928 | 0.995462 | 0.9954312 | 0.9954002 | 23 |
31 | 0.9953692 | 0.995338 | 0.9953068 | 0.9952755 | 0.9952442 | 0.9952127 | 0.9951812 | 0.9951495 | 0.9951178 | 0.9950861 | 20 |
32 | 0.9950542 | 0.9950222 | 0.9949901 | 0.994958 | 0.9959258 | 0.9948935 | 0.9948612 | 0.9948286 | 0.9947961 | 0.9947635 | 19 |
33 | 0.9947308 | 0.994698 | 0.9946651 | 0.9946321 | 0.9945991 | 0.994566 | 0.9945328 | 0.9944995 | 0.9944661 | 0.9944327 | 17 |
34 | 0.9943991 | 0.9943655 | 0.9943319 | 0.9942981 | 0.9942643 | 0.9942303 | 0.9941963 | 0.9941622 | 0.994128 | 0.9940938 | 16 |
35 | 0.9940594 | 0.9940251 | 0.9949906 | 0.994956 | 0.9949214 | 0.9948867 | 0.9948518 | 0.994817 | 0.994782 | 0.994747 | 16 |