When weighing powder substances, static tend to cause unstable reading on an analytical balance, and most annoyingly, causing sample to stuck and disperse around the mouth of test tube.
How do you overcome this problem?
I know company like Shimadzu has a static remover block for this purpose, but it's too expensive to get one.
Thank you for your valuable tips. I will try to weight first on a sample boat before transferring to the glass test tubes. I previously weight directly into the test tube and constantly cleaning and rubbing the spatula with tissue and ethanol, maybe that's what causing the static to be worse.
You may not want to use the following advice if you are weighing hazardous substances: don't wear gloves. They are a big source of static. Check with the lab head whether this is permissible if you want to try it. Wash your hands afterwards.
Otherwise, minimize static by avoiding a lot of motion of the solid in its container. In other words, avoid shaking or tapping the container. Use metal spatulas, not plastic ones. If you are not weighing the solid directly into the final container, use glassine weighing paper rather than a weighing boat. Use the smallest feasible piece of weighing paper, not necessarily a whole one.
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