Sciencemadness Discussion Board

Silver Mirror Coated Glassware

PeeWee2000 - 6-10-2013 at 15:38

Hello fellow Mad scientists today I have succesfully done a silver mirror coating on the inside of a 1000ml RBF and figured I'd share some of the difficulties and a couple pictures of the outcome as I did not find any guides on this website already. Nurdrage has a pretty decent video on youtube for anyone interested in a step by step visual guide.

Here is a picture of the finished product :D

IMG_1135.jpg - 74kB

The procedure I used, it is based on a MIT lab that Ill upload at the end of this post. I found this lab to be very well written and all the credit goes to its author. As for the difficulties I mentioned there were only two.
The first problem I ran into is that the initial coating was not very thick and was hardly reflective at all, this was overcome by repeating the process of mixing all 3 mirroring solutions in the flask twice versus once. Heres a picture showing the lack of coating.

IMG_1124.jpg - 52kB

Another issue I had was that all the precipitate formed after the solutions were mixed formed a big mud ball like blob and scratched the initial mirror coating quite a bit, this was fixed EXTREMELY carefully rotating the flask not allowing the blob to get stuck in one place as well as using a second go with the mirroring solutions. Heres a picture showing some of the scratches mentioned.

IMG_1125.jpg - 42kB

And a final note is that you need to wash whatever it is youre coating extremely throughly or the silver will not stick well. For me I initially washed the flask with soap water until no bubbles formed when more tap water was added, then added acetone and swished around the flask for about 2 minutes, then I drained the flask and washed 3 times with some distilled water. That cleaning has produced very good results for me if anyone has any recommendations for cleanings more suited for this procedure please do share!

The purpose of why I am doing this is I plan on doing some dry distillations that use sodium hydroxide so I wanted to see if this mirror coating will negate the damage that would normally occur to the glassware I'll share the results as soon as I'm done with that project. I originally saw this idea listed in the benzene production thread and figured I'd try it. If anyone has already tried using a mirror coating to protect your glassware please let me know if it didnt work so I can save a flask!

And heres how to make the solutions listed in the lab so you dont have to math :D

1.5M NH4NO3
100mL H2O + 8g NH4NO3
250mL H2O + 20g NH4NO3

2.5M NaOH
100mL H2O + 10g NaOH
250mL H2O + 25g NaOH

.5M AgNO3
100mL H2O + 8.5g AgNO3
250mL H2O + 21.25g AgNO3

5% Dextrose
100mL H2O + 5g Dextrose
250mL H2O + 12.5g Dextrose

Attachment: Silver mirror coating.pdf (316kB)
This file has been downloaded 318 times

[Edited on 6-10-2013 by PeeWee2000]

frenchemist1 - 8-10-2013 at 12:36

As an evidence, silver metal would be easily removed with nitric acid... Of course !

elementcollector1 - 8-10-2013 at 12:45

I'm interested to see if this works out - I'd love to be able to boil NaOH solutions down in regular glassware.

Pyro - 8-10-2013 at 13:07

I don't think a silver layer that thin will work.
you can scratch it off with your nail if it isn't perfectly coated

bismuthate - 8-10-2013 at 13:12

That would an accident just waiting to happen. One scratch in the silver and you will have hot NaOH all over.

elementcollector1 - 8-10-2013 at 13:24

Quote: Originally posted by bismuthate  
That would an accident just waiting to happen. One scratch in the silver and you will have hot NaOH all over.

Could always plate the silver with something stronger, maybe a thick coating of copper?

bismuthate - 8-10-2013 at 14:13

That would work but how do you copperplate glass?

elementcollector1 - 8-10-2013 at 14:15

Quote: Originally posted by bismuthate  
That would work but how do you copperplate glass?

Well, it's silver-plated already, so it's electrically conductive.

bismuthate - 8-10-2013 at 14:31

Good point. I didn't think of that this could open up so many possibilities for me becase I have no metal comtainers but, I do have AgNO3.

PeeWee2000 - 11-10-2013 at 15:41

Well I know its fairly thin but I'm hoping that as long as I am gentle when pouring the chemicals in that it shouldn't damage the coating but this may just be wishful thinking, also I plan on silver coating my condenser and recieving flask too as the distillate is corrosive to glass as well not nearly as much as NaOH though. I'll know soon enough though and the reaction should be proceeding at temperatures well under 100C so hopefully I wont have a hot mess of hot NaOH all over :o I might do a trial run this weekend I'll be sure to let you all know how it goes if I do :)

Dariusrussell - 11-10-2013 at 17:37

I definitely second electroplating the silver, or at least adding a few more layers before doing a trial. Its concerning that you can see through the silver coating in places and etched glass isn't all that great.

PeeWee2000 - 11-10-2013 at 18:00

I already have added another layer and light cannot pass through the silver layer anymore and there are no more visible scratches the second and third pictures were before I added a second layer. But indeed being able to see through it was concerning which is exactly why I added another coating :D

And as for electroplating I'd like to but it wouldn't be the easiest to do being inside the flask and I don't have any readily available copper plating solutions or the tools to do so.

[Edited on 12-10-2013 by PeeWee2000]

bfesser - 13-10-2013 at 08:31

I thought I had posted this a couple days ago, but I guess it slipped my mind. In my topical compendium (link in sig), under <a href="viewthread.php?tid=25000#copper">copper</a>, there are links to a couple topics of interest.

<strong><a href="viewthread.php?tid=21268">OTC Copper Mirror</a></strong>

(I recall seeing another Cu mirror topic, but can't seem to find it at the moment.)

bismuthate - 13-10-2013 at 08:59

I found a video on making silver mirrors here.
This channel is pretty good in my opinion.