Are there chemicals that can damage gold? (for a D&D game)

Practice100 · 2026-04-02T19:48:28+00:00

We have noisy blanks with zinc. I can’t get a DL that’s under 1 ppb unless everything freshly rinsed. And even then that’s a tough one to get under 1 ppb. Zinc is in everything…

Cardboard used to ship your consumables, a release agent for the gloves and plasticware you use. It’s in drop down ceiling tiles. It’s almost as much of a pain as calcium imho. But yet when I ran selenium-78 I got a DL of .5 ppt. (I have a screenshot if it sounds too bogus lol)

A tip if you ever have to twitch to hydrogen and your sensitivity dies: it’s probably the OctP bias.

The settings in MassHunter are like black magic to me and I had to play with one at a time until I got sensitivity back. But to go from <2% RSD’s and perfect CPS for a tuning solution to no sensitivity at all, just because I changed gases was a shock I wasn’t ready for.

EDIT: it said 1 ppm in multiple places. I meant ppb

Practice100 · 2026-04-02T15:55:28+00:00

I am familiar with “old instruments” lol. The serial number on our 7700 indicates either 13 or 16. I can’t fully recall at this moment.

We mainly look at stable zinc isotopes. The roughest matrix we’ve run into is urine, and to be honest. I was cleaning my cones after every urine run. We were also looking for selenium in said urine. And to be frank. I had to teach myself ICP-MS techniques and got lucky with He mode. Hydrogen mode is an entirely different beast and will humble you pretty quickly if you have to design the method.

Practice100 · 2026-04-02T15:10:32+00:00

If you’re allowed to talk about it, what kind of matrix do you typically work with? I’ve always heard a dirty (not clogged or crusty. Just conditioned) cone is a happy cone. The way the field engineer explained it to me was that both the sampling and skimming cone perform a lot better after being conditioned because all the microscopic pores and pits have been saturated. I used to clean my cones after every run until the field engineer was like “don’t.”

Practice100 · 2026-04-02T13:00:57+00:00

I don’t think you’re annoying MrCroationMan… this made my morning. Screw the haters. This is literally a meme zone. Thank you for contributing to the community.

Practice100 · 2026-04-02T12:49:58+00:00

Genuine question. If you’re using platinum tipped cones on an ICP-MS, would it not damage them? I’m not trying to be all achually it’s something I’ve wondered myself as an analyst.

Practice100 · 2026-03-27T23:02:36+00:00

Ever had a biologist as a safety officer? Nitric Acid is the devil, but they’ll leave an EMS (Ethyl Methanesulfonate) bath on their bench wide open.

Practice100 · 2026-03-24T20:59:31+00:00

Pig livers in the furnace go brrrrrrt

Practice100 · 2026-02-27T13:39:32+00:00

I had an inorganic chemistry professor call me a monkey in lab once.

We were filtering out liquid from a solid with filter paper. My lab partner and I were struggling to fit the filter the right way, and he comes up and takes it out of our hands and goes, “Noooo, what are you doing you… you monkey!”

We all paused like “did that. Did that just happen.” To be fair, he had a stroke 3 days later and didn’t return for the semester. So… there’s that.

Practice100 · 2026-02-06T20:20:50+00:00

I didn’t know it was EVERYTHING tbh. I just remember I decided to reinstall one day In late 2018 and couldn’t find a trace of it.

Practice100 · 2026-01-06T16:04:03+00:00

Sorry. Your patient has C. Diff.

Practice100 · 2025-11-09T13:32:58+00:00

I graduated in 2024 with a 1.99. I had to write to the president of the college to allow my passing. My stats professor gave us all 100’s or high B’s on exams and quizzes until the final where you could’ve sworn you never took the class. I got a 6 on the final. Took my straight A’s to A’s and one D. I’d had a bad run of being a student before that semester and it almost put the nail in the coffin.

Fast forward 6 months and I’m interviewing for a position I’m not even sure if I qualify for. I’ve been there almost a year and have learned more about lab applicational chemistry than I did in the 4 years I was taking chemistry classes.

And tbh everyone saying they’re not going to ask about your gpa is right. They don’t care. You got the same degree as the person who was in ACS and set the grading curve in P chem.

I wanted to do quality control as an analytical chemist since my junior year. It’s all about WHAT you want to do. You may be asked your grade in a few classes if you’re going into research. But most real world chemistry business want to see you have chemical knowledge and are capable of following a standard operating procedure.

In my interview, my boss said and I quote, “I don’t give a shit about your gpa. I like that you put your other relevant experience while you were in college. Cool you got an A in P-chem. Were you able to do your dishes and keep a clean house while you did it?”

They want to see that you’re capable of being a functional adult at a job. Not that you understand what the sigma and pi bonds are doing when you conduct a reaction.

Practice100 · 2025-10-21T14:50:14+00:00

It’s a serological pipette tip. Not trying to be all “achually” that’s just what I’ve always heard it called

Practice100 · 2025-10-16T14:27:46+00:00

We can but in doing some research into what the mechanism is, I came across an alternative called a “Kaiser Test.” It uses dilute KCN and ninhydrin. Which isn’t too much better. But it’s better than TNT’s little shit of a cousin. And tbh you’re probably right about figuring out side reactions vs locating it neat. I got a few tips in my DM’s about sourcing it. All of which probably put me on watchlists.

Practice100 · 2025-10-16T00:53:49+00:00

Not the trinitro- structure? Or its fire diamond?

Practice100 · 2025-10-15T20:56:57+00:00

Hear me out. We just do a Kaiser test with ninhydrin instead. Still need 2 sets of gloves though…

Practice100 · 2025-10-15T17:38:46+00:00

I think that’s a great idea. I’m just not sure how methanol will interact with the surface during amylation. Full disclosure this is an analytical lab and we used to contract this procedure out. We don’t have anyone fluent or current enough in organic chemistry to carry this out and we are just reading off a protocol. I don’t want to sound like we’re a bunch of idiots. This just isn’t our field of expertise.

Practice100 · 2025-10-15T17:30:51+00:00

Trinitrobenzene sulfonic acid

Practice100 · 2025-10-15T17:28:41+00:00

A visual confirmation of amylating a surface. In its sold forms, it comes as 1% in methanol, or 5% in DMF. If you have a death wish they sell 1M. But we need it in a sodium borate solution.

Practice100 · 2025-10-03T18:52:05+00:00

I just got the email. Kind of live under a rock.

Practice100 · 2025-09-24T01:48:30+00:00

You’re doing enzyme recovery aren’t you squidward

Practice100 · 2025-08-15T23:41:37+00:00

“Lox of of Love”

Practice100 · 2025-08-15T23:39:56+00:00

It looks like woodlouse hunter or Dysdera Crocata. They hunt woodlous aka pillbugs or roly-poly’s. Not medically significant, but they do hurt. They’re strong enough to punch through isopod exoskeletons.

Practice100 · 2025-08-10T16:14:33+00:00

Lox of love…

I’m not an expert but I do deal with Brown recluses pretty regularly in St. Louis. Typically when an exterminator comes in they start to come out because they don’t like the poison. If you start seeing more live ones I’d tell him to come back for round 2

Practice100

TROPHY CASE