氫氧化鈉在空氣中容易潮解,現(xiàn)在實驗室中只有片狀的氫氧化鈉,但只需極微量如29 mg,故不便稱量,請問如何把片狀氫氧化鈉簡單的制成粉末狀的氫氧化鈉?而又不會被潮解引起稱量不準(zhǔn)確。
It's very easy to make sodium hydroxide into flake powder in the laboratory, but it's very inconvenient to weigh it in the air? And will not be deliquescence caused by inaccurate weighing.
氫氧化鈉與氫氧化鈉在普通實驗室條件下是必然要潮解的,粉碎的狀態(tài)下潮解更快,不可能準(zhǔn)確稱量。所以如果只是為了在普通條件下準(zhǔn)確稱量而想要粉碎片狀氫氧化鈉的話,就不用考慮了。那么如何準(zhǔn)確得到一定量的氫氧化鈉呢?
Sodium hydroxide and sodium hydroxide must be deliquesced under ordinary laboratory conditions, and the deliquescence is faster in the crushing state, so it is impossible to weigh accurately. So if you want to crush Flake sodium hydroxide just for the sake of accurate weighing under ordinary conditions, you don't need to consider it. So how to get a certain amount of sodium hydroxide accurately?
方法 1 在干燥氣氛下操作,簡單的就是在惰性氣體保護(hù)下的手套箱或者手套袋里稱量;
Method 1 was operated in a dry atmosphere, which was simply weighed in a glove box or glove bag under the protection of inert gas;
方法 2 考慮到氫氧化鈉一般在溶液中使用,那么可以稱取大致的量,溶解于相應(yīng)的溶劑中,然后用滴定的方法確定真實濃度,滴定的具體流程需要根據(jù)溶劑的種類確定,相關(guān)信息網(wǎng)上有大量可以獲取,另外,注意密封容器以保護(hù)溶液不被空氣中的二氧化碳所破壞;
Method 2 considering that sodium hydroxide is usually used in solution, the approximate amount can be weighed and dissolved in the corresponding solvent, and then the true concentration can be determined by titration. The specific process of titration needs to be determined according to the type of solvent. There are a lot of relevant information available on the Internet. In addition, pay attention to sealing the container to protect the solution from being damaged by carbon dioxide in the air;
如果你足夠大條地覺得10%以內(nèi)的誤差可以接受(俺大條地趕腳其實一般都可以啦),那就弄個spatula搗搗碎(注意不要吸入氫氧化鈉粉末哦,很嗆人的)再快速稱量吧。
If you are big enough to think that the error within 10% is acceptable (in fact, it's OK for me to make a large strip), then mash it with spatula (pay attention not to inhale sodium hydroxide powder, which is very irritating) and then weigh it quickly.