I am conducting an organic synthesis experiment involving 2,3,5-tribromothiophene. The melting point of 2,3,5-tribromothiophene is about 25-28 ℃, so it melts easily during weighing. Whenever I weigh this compound, it melts soon and wet the weighing paper. So there arises big uncertainty in weight of compound. How can I weigh the compound that melts at room temperature and move it to the reactor with minimum loss? Is there no other way but to weigh as quickly as possible?

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    $\begingroup$ How about using a plastic weighing boat and flush the sample into the reactor with the corresponding solvent? $\endgroup$ – andselisk May 11 at 10:41
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    $\begingroup$ Weigh it as a liquid, pipette it into a tared vial, dissolve in reaction solvent and add to reactor. $\endgroup$ – Waylander May 11 at 10:56
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    $\begingroup$ Similar to weighting boats of plastic or glass, a watch glass may do the job, too. Depending on scale and design of the balance, a beaker (there are already ones for about 20 mL) may do the job, too. $\endgroup$ – Buttonwood May 11 at 11:29
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    $\begingroup$ @andselisk Yes, but not with dichloromethane... Learnt that the hard way! $\endgroup$ – orthocresol May 11 at 12:30
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    $\begingroup$ @orthocresol On the positive side, you also discover a nice "glue" for many plastics;) $\endgroup$ – andselisk May 11 at 12:34

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