[HailoMan]

Hi all,

Apology in advanced if this is a silly question.
I am running some ultrasonication experiments in the lab and need to measure the temperature of the solution.

Is it safe / sensible to use the standard mercury thermometer for temperature measurement?
I was thinking that mercury might absorb the ultrasound energy better than the solution itself, which can be either dangerous (if the temperature goes up that fast) / give erroneous reading.

Thank you

[Arkcon]

I'm not sure, but my gut reaction is the same is yours, a hollow glass liquid-filled tube in an ultrasonic bath seems like the potential for problems.  You might want to look into a thermocouple thermometer, or at least be sure your thermometer is alcohol filled instead of mercury.  Also, the thermometer should be in a vessel with the sample, not the bath.  Still, I wouldn't leave the thermometer in place, I'd just check intermittently.

[Mitch]

The mercury sounds like a really bad idea. Most EH&S departments will replace them for ethanol thermometers for free.

[HailoMan]

Thanks for the responses.
I wasn't planning on putting the thermometer in place continuously, but I was a skeptical on even putting in a glass filled with liquid metal onto ultrasonicator, even if it's intermittent.
I've seen people do it in the lab and I've wondered if it's quite the right thing to do.

[curiouscat]

How accurate must it be? Thermocouples are cheap these days.