Amber dropper bottles

[RosalieL]

I need to buy some more droppers. I've had a look through a few threads. What are people's opinions of the black silicon droppers vs the old red ones? The droppers need to fit in the unitrays. Do the stuhl bottles fit in these trays? What's better value for money? I'm keen to keep using the amber glass droppers for aesthetic reasons (I don't have the budget to replace them all)... has anyone found a good place to get the amber bottles? The places I've looked at range from $215 - $250 for 100 bottles with droppers.

[Merilyn1]

I think Bigmack did a good test on the black ones. Maybe search for that or the good man will jump in with his findings.

I found the black, silicon ones pretty useless. They are too small for the 50mL droppers. Are okay on the 25mL but there are a lot of chemicals they don't like and they disintegrate. They don't fit into the dropper cap as well as the rubber ones, even on the 25mL.

The really disappointing thing is we can now no longer buy just the red rubber teats. You have to buy the whole dropper assembly. I have a stash but now if the rubber perishes, I throw out the whole dropper otherwise I'm going to be overrun with white plastic caps and the glass tube.

I use the amber glass droppers. It is what we have, what we are all used to using. You can buy the bottles and dropper assemblies separately (try SSA and Haines).

[bigmack]

I've got mine from Haynes recently .
I got some from Serata MTA but they have a funny size dropper lid that doesn't fit anything else.

The Black Silicone teats from MTA are quite resistant to most things except acid . They quickly perish with Acid . The Red Rubber ones are better for Acid still .
Some of the Black Teats seem a bit loose on some glass droppers and occasionally don't seal enough to suck up . They also don't suck up as much as a Red Rubber ones . Other than that , they seem to last better .

Edit:
Posted with Merilyn . Sounds like you have similar feelings on them

[RosalieL]

Science supply looks like a winner! Thanks Merilyn! I always forget about them!!! And it looks like they have the caps as well cheering!!

[Merilyn1]

I do make my rubber dropper assemblies last a bit longer by swapping the droppers over to solid caps when not being used. There are a few chemicals that get trotted out four times (for each class) once a year and sit, sulking away the rest of the time. Vinegar, acetic acid, nitrates and copper seem to be the most destructive.
I actually buy most of my equipment from SSA. They usually have a good range of quality and prices to fit my budget. As with most of the suppliers, they are always good to deal with. I like Haines too, Victor has helped me out by doing special orders for certain models we needed.

[RosalieL]

Yes, I used caps a lot at my previous school. I've struggled to find a supplier for them since coming to this one though! It is possible I was pointed in the direction of science supply back when I was looking and didn't get a chance to do anything about it at the time... I don't suppose you know what cap I need to order to fit the 50ml dropper bottles? I have emailed them to ask but don't expect to hear back too quickly.

[Merilyn1]

Gave you a bum steer - I've been buying the caps from Haines and they have have them for 25 and 50mL bottles. I think the SSA ones are wadded which I don't buy because of contamination problems going from one bottle to another and not being able to clean them properly. The unwadded ones work just fine.

[Anna Z]

I do make my rubber dropper assemblies last a bit longer by swapping the droppers over to solid caps when not being used. There are a few chemicals that get trotted out four times (for each class) once a year and sit, sulking away the rest of the time. Vinegar, acetic acid, nitrates and copper seem to be the most destructive.
I actually buy most of my equipment from SSA. They usually have a good range of quality and prices to fit my budget. As with most of the suppliers, they are always good to deal with. I like Haines too, Victor has helped me out by doing special orders for certain models we needed.

This is us also...exactly same practice and supplier.

[RosalieL]

The Haines caps are very expensive though! I just checked and SSA plain cap (non-wadded) is 15c vs Haines 60c each! Does “wadded” mean the little plastic bit on the inside of the lid? I have often wondered why they are called that! I had actually thought it was the grippy sides…

[RosalieL]

Do you guys swap your droppers out for caps for all concentrations of acid or only the stronger ones?

[Anna Z]

Do you guys swap your droppers out for caps for all concentrations of acid or only the stronger ones?

Just the stronger ones for us.

[Merilyn1]

I just buy the cheaper ones from SSA, they work fine. I always thought the wadding would get contaminated and be difficult to clean.
I usually swap out the things that "eat" the rubber teat - most of the nitrates (silver nitrate is fine), iodine, nitric acid (not that anyone uses that anymore), sulfuric acid, stronger concentrations of HCl and anything with copper in it.

[RosalieL]

Do you guys swap your droppers out for caps for all concentrations of acid or only the stronger ones?

Just the stronger ones for us.

Is 4M HCl ok or would you put a cap on that? Thanks! I'm slowly re-labelling and cleaning out the acids and don't want to lose any more droppers to acids destroying them! I took so many droppers out that had become solid and some even had acid crystals (like stalagmites!) growing out of them! I'm also reducing the number of concentrations we have on hand. 0.5, 0.1, 1, 2 and 4M for each acid. Does that sound reasonable?

[Merilyn1]

Regarding the concentrations of acids, we generally have 0.1M and 1M in droppers. I do also have 2M HCl in droppers. A coincidence that I read this now as I've just emailed a teacher who wanted 0.5M solutions (at short notice) telling him he could have 0.1M and in future if he wanted 0.5M I would organise it but it would not be in droppers because no one ever used it.
So, my suggestion is to work out what your teachers need. You can do a search in Riskassess to see what they have been using in the past. If you have 1M, it is a quick job to dilute it to some of the other lower concentrations. If your teachers are happy with it in stock bottles, this will save you a bit of work, especially for the rarely used concentrations.

[RosalieL]

Interesting... That's what we had at my prevous school (0.1 and 1M) but they seem to use a variety of concentrations here! Maybe because they were just "there"? I don't know... we've got 5M, 6M and 2.5M of some things.... I just thought maybe things had changed over the years I wasn't working in science! I'll keep the HCl ones as I've done them now (and they seem to be the most frequently used) and just do 0.1 and 1M for the other acids. As you say, I can easily make other concentrations if required. Simplifying is always good!

[Merilyn1]

I think they just copy previous experiments without thinking too much about what they need. Limit supply and they'll adapt. Probably, my first port of call would be to let the teachers know you are streamlining. Most of them won't say anything so you can go ahead and wait for the tears later

[Anna Z]

Interesting... That's what we had at my prevous school (0.1 and 1M) but they seem to use a variety of concentrations here! Maybe because they were just "there"? I don't know... we've got 5M, 6M and 2.5M of some things.... I just thought maybe things had changed over the years I wasn't working in science! I'll keep the HCl ones as I've done them now (and they seem to be the most frequently used) and just do 0.1 and 1M for the other acids. As you say, I can easily make other concentrations if required. Simplifying is always good!

[RosalieL]

Ok now for the next stage of my prep-room revamp.... how do you store your droppers? As in shelving solutions. I have the unitrays for keeping sets together. I googled dropper storage system just to see what came up and got a heap of YouTube videos for Minecraft Not quite what I was looking for!

[Labbie]

WE had them in A-z order in a cupboard, 10 sets via a tray from Haines (I think it was) Really only needed 8 but teacher could see start away if any where missing. As they are only small amounts, they could all be stored together, not in class's if that makes sense?

[Merilyn1]

I have an ample chem store so my droppers are stored in there. In Unitrays and with the DG class of the solid/concentrate.
I'm not sure how you got to Minecraft!