A little tip for volumetric analysis!
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I’m not very dexterous; when performing titrations, I used to get extremely tired from shaking the Erlenmeyer flask by hand. So I came up with a trick: placing the Erlenmeyer flask on a magnetic stirrer so that there’s no need to shake it by hand, which is much more convenient； Connect a silicone tube from the end of the burette, install a solenoid valve, and control the addition of the solution by switching the solenoid valve. In this way, one only needs to press the solenoid valve switch with one hand while watching the color changes; there’s no need for the same level of effort as before, which is perfect for a lazy person like me! Let me share it with everyone! However, once I went to the Tianjin Alkali Plant and saw that their analysts also used magnetic stirrers for mixing, though solenoid valves were not yet in use. This post was last edited by shuchang on 2008-10-15 14:41]
A magnetic stirrer can be used, and since the solenoid valve is connected to a latex tube, I think it’s best to omit it in analyses where high accuracy is required. Hehe
Too smart – it saves everyone from getting shoulder periarthritis
The magnetic stirring method is good; the idea of using solenoid valves must be based on the requirement of ensuring measurement accuracy!
Connect a silicone tube from the end of the burette, install a solenoid valve, and control the addition of the solution by switching the solenoid valve. The original poster is really amazing! I would like to know how you install solenoid valves What is the model of the solenoid valve?
The ZDF-Z1/1 combined multi-functional solenoid valve offers four flow rates: fully open, wide open, narrow open, and fully closed. Is this type of solenoid valve being used? In this way, the amount of solution can be controlled; it would be even more accurate if there were a solenoid valve equipped with a metering device!
It seems that practice really does make perfect~ Everyone should share this kind of experience more~
Although this method is good, it has its drawbacks. If the latex tube contains ionic solutions, it can affect the accuracy of the results. Additionally, sometimes manual stirring works better than using a magnetic stirrer. Moreover, when using solenoid valve switches, it’s easy to add too much – even half a drop or a quarter of a drop – which can affect the endpoint and thus the accurate reading. Therefore, it’s fine to use this method occasionally, depending on the circumstances
Indeed, there is knowledge to be found in everything if you pay attention
I think the method suggested by the original poster works well in the first half of the titration process, but it becomes problematic in the latter half. Controlling the solenoid valve makes it difficult to ensure the addition of small doses, or even very small doses, which may directly affect the determination of the titration endpoint. An excess of titrant is very likely.
Magnetic stirrers are not as effective for reactions as manual stirring; this experience should not be promoted