[Alt-photo] ammonio-nitrate(and high school shenanigans)

Greg Franco gfrancophoto at gmail.com
Sun Sep 18 01:51:48 UTC 2016


Okay.. so nothing really about the ammonio-nitrate.
But this thread reminded me of a Spanish teacher I had that would sense when we were getting bored and he would suddenly jump on the desks and walk across them all or try to beat his own spit wad record by trying to make one stick to the back wall from a new distance.  But one time he closed all the drapes...back then they were light blocking because sometimes films were shown in the classroom... he then bunched up the curtains to make a little opening and then ran outside to the ivy covered hill just outside the class.... and there he was in full color upside down and backwards jumping up and down on the wall opposite the windows.  That was my first exposure to a camera obscura! 

Greg.

>This is exactly why I love this list. Thanks Jim for the chemistry knowledge. Peter, that is the funniest story. >Nowadays I suppose if we did that we would get expelled or the hazmat team would be called in. The most I ever >did was brush rubber cement all over my desk roll it up in a ball, and throw it at the blackboard while the teacher >had her back to us. It bounces wonderfully. Why she didn’t smell something going on is beyond me.
>Chris


>> It might have been rather dangerous but we used to coat the tip of piece
>> of chalk with the damp precipitate from silver nitrate and ammonia and
>> let it dry - and enjoy the reaction when our chemistry teacher wrote on
>> the chalk board.
>> Peter
On 9/17/2016 11:32:38 AM, alt-photo-process-list-request at lists.altphotolist.org <alt-photo-process-list-request at lists.altphotolist.org> wrote:
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Today's Topics:

1. Re: ammonio-nitrate (Christina Z. Anderson)
2. Re: My gum book arrived! (Christina Z. Anderson)
3. Dichromates, REACH and the EU (John Brewer)
4. Re: Dichromates, REACH and the EU (Laura V)


----------------------------------------------------------------------

Message: 1
Date: Sat, 17 Sep 2016 06:49:28 -0600
From: "Christina Z. Anderson"
To: Alt List
Subject: Re: [Alt-photo] ammonio-nitrate
Message-ID:
Content-Type: text/plain; charset=windows-1252

This is exactly why I love this list. Thanks Jim for the chemistry knowledge. Peter, that is the funniest story. Nowadays I suppose if we did that we would get expelled or the hazmat team would be called in. The most I ever did was brush rubber cement all over my desk roll it up in a ball, and throw it at the blackboard while the teacher had her back to us. It bounces wonderfully. Why she didn’t smell something going on is beyond me.
Chris


On Sep 16, 2016, at 5:15 PM, Jim Patterson via Alt-photo-process-list wrote:

> You are correct. The 3 highly explosive silver compounds that are confused are silver nitride (Ag3N) (formerly called fulminating silver), silver azide (AgN3), and silver fulminate (AgCNO). Silver nitride is the one formed when silver nitrate and ammonia are mixed in certain ratios. I have witnessed that one first hand as I said before. I contributed to the confusion by equating silver fulminate with fulminating silver. Chlorides precipitate silver chloride and probably reduce the risk of explosion with salt printing, but a wrong mix, when evaporated to dryness can be a problem.
> Jim
>
> Sent from my iPhone
>
>> On Sep 16, 2016, at 5:11 PM, Charles via Alt-photo-process-list wrote:
>>
>> While I have no intention of ever making it I am confused by the fact that Wikipedia insists that silver fulminate is made with nitric acid, which is a long way from ammonia. Charles
>>
>> -----Original Message----- From: Peter Marshall via Alt-photo-process-list
>> Sent: Friday, September 16, 2016 12:57 PM
>> To: alt-photo-process-list at lists.altphotolist.org
>> Cc: Peter Marshall
>> Subject: Re: [Alt-photo] ammonio-nitrate
>>
>> It might have been rather dangerous but we used to coat the tip of piece
>> of chalk with the damp precipitate from silver nitrate and ammonia and
>> let it dry - and enjoy the reaction when our chemistry teacher wrote on
>> the chalk board.
>>
>> But although in small quantities it is relatively harmless I think it
>> best to avoid ammoniacal silver nitrate on safety grounds. But the
>> occasional explosion certainly made chemistry lessons more interesting.
>>
>> Peter
>>
>>> On 16/09/2016 18:13, Marek Matusz via Alt-photo-process-list wrote:
>>> Chemistry in the days was so much fun.
>>> Just lab experiments no iPads
>>>
>>> And making silver mirrors was always great
>>>
>>> Marek
>>>
>>> Sent from my iPhone
>>>
>>>> On Sep 16, 2016, at 12:01 PM, Jim Patterson via Alt-photo-process-list wrote:
>>>>
>>>> Hi Chris,
>>>> Glucose is a reducing sugar. It is a reducing agent in an alkaline enviroment with heat. It reduces the Ag+ ion to Ag (silver metal). It also reduces a copper II sulfate solution to copper I oxide (a yellow precipitate) which is the basis of Fehling's Test and Benedict's Test for urine sugar. A commercial version for diabetics used to be available in pharmacies as Clinitest tablets.
>>>> Jim
>>>> ---- "Christina Z. Anderson via Alt-photo-process-list" wrote:
>>>>> Well, Jim there you have it.
>>>> I have no desire to make a process more complex just for historic purposes when it is a) not necessary and b) dangerous. Because if there is a mistake to be made, a student will do it.
>>>> Thanks for this!
>>>> But I’m dying to know why glucose plated out the silver?
>>>> Chris
>>>>
>>>>> On Sep 16, 2016, at 10:41 AM, Jim Patterson via Alt-photo-process-list wrote:
>>>>>
>>>>> Hi Chris & all,
>>>>> A word of caution. Ammonia + silver nitrate can produce silver fulminate which is very explosive and very sensitive to jarring, heat. We used to do the "silver mirror" test for glucose in the urine (back in the old days). It was done by adding a ml of silver nitrate solution to a test tube, then drops of ammonia until the brown precipitate first formed dissolved, then a ml of urine was added and it was heated over a bunsen burner. If glucose was present, the silver plated out on the bottom of the test tube. We were warned not to mix up a stock solution and to always wash the waste down the drain promptly with a lot of water. Once a lazy student let it sit in the test tube rack until next lab when it had evaporated to dryness. The student dropped the tube in the sink and it exploded. Fortunately no one was hurt.
>>>>> Jim Patterson
>>>>>
>>>>> ---- "Christina Z. Anderson via Alt-photo-process-list" wrote:
>>>>>> I’ve compiled some notes, so bear with my truncated note taking skills, but here is some stuff on ammonio-nitrate which spellcheck seems to want to change to ammonia.
>>>>> I was planning on trying it out, but I just don’t see a reason to make the silver nitrate formula more complex than just adding silver nitrate to water.
>>>>> Citric acid was added often, in fact about 30% of the 80 formulas I recorded have added citric. But I also don’t see a need for that, especially if citric acid or sodium/potassium citrate are used in the salt formula. Someone may convince me differently though, but Young agrees.
>>>>> The paper that turns brown for me is invariably the plain salted ones with no citrate. The others stay unfogged for the whole day and even into the next, but then again I am not silvering 100 sheets for the week like they probably did back in the day when paper keeping was a big deal.
>>>>> Chris
>>>>>
>>>>> 1854 JPS Vol1 “Hints on Positive Printing” pp. 170–171 by W. Teasdale. Why ammonio-nitrate is objectionable. It cannot be used with albumen. It has to be washed before being fixed. Have to take great care to wash fingers after handling or brown stains will occur. The paper won’t keep.
>>>>> Howlett 1856 p. 12 The ammonio-nitrate was first described by Taylor. It is quicker and it prints black and white more easily. Formula is on this page.
>>>>>
>>>>> Sparling 1856 pp. 153–166 1gr gelatin, 10grs am or sod chlor water 1 oz. Then use the normal silver solution of 60grs/1oz or the ammonio nitrate solution (which he gives a formula for here; he also says that if the brown precipitate never forms it is because there is a lot of nitric acid in the solution and it would require therefore lots of ammonia to get the precipitate but this doesn’t happen frequently. Also, all say to keep ammonio-nitrate in a dark place because it is more prone to reduction than silver nitrate. Also, that brush is better than tray because by tray the ammonio-nitrate reacts with the salt and produces reddish pink half-shadows. Also, oddly, that ammonio-nitrate paper doesn’t keep but a few hours whereas gelatin/silver nitrate paper keeps a few days).
>>>>>
>>>>> 1868 Illustrated Ph Printing on Mat Paper by George Dawson pp. 359–360. He dismisses ammonio-nitrate paper.
>>>>>
>>>>> Harrison History 1888 p. 83 1842 ammonio-nitrate Dr. A. S. Taylor (and A. Smee and Mr. Collen about the same time) which cannot be used with albumen because it dissolves the egg white.
>>>>>
>>>>> 1908 American Photography Thomson, James Vol II No. 3 March 1908 Plain Salted Paper pp. 121–126 He says that ammonio-nitrate is used to make the paper more sensitive and to give richer prints, but the paper doesn’t keep longer than 24 hours and it is best to use the fuming method instead.
>>>>>
>>>>> Reilly 1980 64 the ammonio-nitrate bath was very popular 1840–1860 but it had some disadvantages: prints yellowed quickly and the solution discolored quickly. It also dissolved the albumen off the paper. It also produces “fulminating silver” which is explosive if a solution is boiled down.
>>>>> _______________________________________________
>>>>> Alt-photo-process-list | altphotolist.org
>>>>>
>>>>>
>>>>> _______________________________________________
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------------------------------

Message: 2
Date: Sat, 17 Sep 2016 07:11:40 -0600
From: "Christina Z. Anderson"
To: Alt List
Subject: Re: [Alt-photo] My gum book arrived!
Message-ID: <5b9fc201-540b-408c-ac60-bfe4fa46c8fe at gmail.com>
Content-Type: text/plain; charset=windows-1252

Thanks for the praise, John, and glad you got it.
Your work in it is quite intriguing and makes me want to go to that place!
How do I do manage? An unhealthy ability to hyper focus for an extended period of time, abandon a social life, be ok with sitting for days weeks months in a chair with a laptop, a husband who manages everything else... It is not a lifestyle for everybody and there is no glamour in it. I bet your wife feels the same way, being an author? I have her book to read on my laptop for when I finish salt research! That’ another thing that goes out the window: fiction reading.
But such a great reward it is to have all that time packaged in one little neat 8x10x1” square. And it helps that I love research; it’s a treasure hunt.
Today I get to PLAY though. Heading out to Rochester NY to take a salt and albumen workshop with Mark Osterman at the George Eastman House! And see historic salt prints! And photograph pages from the one book I can’t get anywhere else but the Eastman library, too, while I’m there!
Chris

On Sep 16, 2016, at 5:11 PM, johnbrewerphotography--- via Alt-photo-process-list wrote:

> I've been on holiday and just this week picked up my book from the Post Office. What a wonderful book Chris! How you manage to have a family life, teach and write such an intensive book on gum is beyond me.
>
> For those who've tried but failed to make a gum print and have been put off because of frustration this highly illustrated book is the definitive guide. And no doubt will be for many years to come.
>
> Thanks Chris!
>
> John
>
> Sent from my iPhone
> _______________________________________________
> Alt-photo-process-list | altphotolist.org



------------------------------

Message: 3
Date: Sat, 17 Sep 2016 17:05:25 +0100
From: John Brewer
To: Alt List
Subject: [Alt-photo] Dichromates, REACH and the EU
Message-ID: <368db0f6-1f39-45a9-91c7-30327da1fac2 at gmail.com>
Content-Type: text/plain;charset=utf-8

Hello dichromate users

I wrote to the UK Health and Safety Executive a while ago and received the reply below. As a tutor, practitioner and supplier of some alt process chemistry I can buy dichromates without filling out the crazy form as it can be used for 'research and development'. Note that doesn't mean I can supply. I forwarded this email to my supplier who deals directly with Sigma and they have no problem selling it to me provided it's in small quantities. I'm not sure if this will apply to individuals but it's worth quoting the information below to your supplier.

I hope the email below helps some of you European dichromate users.

Best wishes

John

Dear John,

As you note, potassium chromate is listed in Annex XIV of REACH and is therefore subject to authorisation. The sunset date for potassium dichromate is 21 September 2017. After this date, it will not be permitted for a company (including self-employed individuals) to use the substance in the EU, or place the substance on the market for a use, unless they have authorisation from the European Commission. It is technically challenging and expensive to apply for authorisation.

The ideal option beyond the sunset date would be to use a viable, safer alternative to potassium dichromate. Perhaps this has already been addressed in your industry? It may be worth talking to other painters and/or a relevant trade association to find out if others have already considered this issue and the approach they are taking.

Alternatively, especially as you use such a low volume, you might consider whether any of the exemptions from authorisation might apply here. They can be found in our bitesize leaflet on authorisation (leaflet number 19 at: http://www.hse.gov.uk/reach/bitesize.htm). For example, Article 56(3) is clear that authorisation does not apply to the use of substances for scientific research and development (SRD).

You mention that you are a tutor. It is possible that your use of the substance (as a tutor) could be considered as SRD. SRD is a defined term in REACH [Article 3(23)] as “scientific research and development: means any scientific experimentation, analysis or chemical research carried out under controlled conditions in a volume less than 1 tonne per year”.
· As well as covering chemical research, it also applies to scientific experimentation or analysis;

· The definition includes an ‘or’ and an ‘any’ so logically, the ‘any’ applies to all three terms in the list; i.e., any scientific experimentation, any analysis, and any chemical research;


However, it would be for you (and others who use chromium compounds in a similar way) to decide whether your use meets any of the exemptions. Should you decide to continue to use the substance after the sunset date, we would recommend that you document any decisions made in case you are ever challenged by a Regulatory Authority.

Authorisation can be applied for by the user of the chemical or by the EU-based supplier on behalf of the people they supply to. Therefore, if you decide that the criteria for exemption are not met (i.e. that authorisation is required), the next step you take will be determined by where your supplier is based. If your supplier is based in the EU, we would recommend that you contact your supplier to find out whether the supplier has applied for authorisation, and whether you can benefit from this.

If you source the substance directly from outside the EU, the duty to apply for authorisation would fall to you. However, we appreciate that this may be an unrealistic task. Please don’t hesitate to get back in touch with the helpdesk should you wish to discuss this further.

I hope this helps.

Kind regards,

Laura
------------------------
Laura McCabe
REACH & CLP Helpdesk
Chemicals Regulation Division

HSE, Redgrave Court, Bootle, Merseyside L20 7HS



Sent from my iPad

------------------------------

Message: 4
Date: Sat, 17 Sep 2016 18:31:59 +0000
From: Laura V
To: alt-photo-process-list at lists.altphotolist.org
Subject: Re: [Alt-photo] Dichromates, REACH and the EU
Message-ID: <0b26b58e-55bc-aadb-ef14-b5ed223890ae at lavatop.com>
Content-Type: text/plain; charset=utf-8; format=flowed

Thanks John...so we are scientists now and not artists?

Laura

On 9/17/16 4:05 PM, John Brewer via Alt-photo-process-list wrote:
> Hello dichromate users
>
> I wrote to the UK Health and Safety Executive a while ago and received the reply below. As a tutor, practitioner and supplier of some alt process chemistry I can buy dichromates without filling out the crazy form as it can be used for 'research and development'. Note that doesn't mean I can supply. I forwarded this email to my supplier who deals directly with Sigma and they have no problem selling it to me provided it's in small quantities. I'm not sure if this will apply to individuals but it's worth quoting the information below to your supplier.
>
> I hope the email below helps some of you European dichromate users.
>
> Best wishes
>
> John
>
> Dear John,
>
> As you note, potassium chromate is listed in Annex XIV of REACH and is therefore subject to authorisation. The sunset date for potassium dichromate is 21 September 2017. After this date, it will not be permitted for a company (including self-employed individuals) to use the substance in the EU, or place the substance on the market for a use, unless they have authorisation from the European Commission. It is technically challenging and expensive to apply for authorisation.
>
> The ideal option beyond the sunset date would be to use a viable, safer alternative to potassium dichromate. Perhaps this has already been addressed in your industry? It may be worth talking to other painters and/or a relevant trade association to find out if others have already considered this issue and the approach they are taking.
>
> Alternatively, especially as you use such a low volume, you might consider whether any of the exemptions from authorisation might apply here. They can be found in our bitesize leaflet on authorisation (leaflet number 19 at: http://www.hse.gov.uk/reach/bitesize.htm). For example, Article 56(3) is clear that authorisation does not apply to the use of substances for scientific research and development (SRD).
>
> You mention that you are a tutor. It is possible that your use of the substance (as a tutor) could be considered as SRD. SRD is a defined term in REACH [Article 3(23)] as “scientific research and development: means any scientific experimentation, analysis or chemical research carried out under controlled conditions in a volume less than 1 tonne per year”.
> · As well as covering chemical research, it also applies to scientific experimentation or analysis;
>
> · The definition includes an ‘or’ and an ‘any’ so logically, the ‘any’ applies to all three terms in the list; i.e., any scientific experimentation, any analysis, and any chemical research;
>
>
> However, it would be for you (and others who use chromium compounds in a similar way) to decide whether your use meets any of the exemptions. Should you decide to continue to use the substance after the sunset date, we would recommend that you document any decisions made in case you are ever challenged by a Regulatory Authority.
>
> Authorisation can be applied for by the user of the chemical or by the EU-based supplier on behalf of the people they supply to. Therefore, if you decide that the criteria for exemption are not met (i.e. that authorisation is required), the next step you take will be determined by where your supplier is based. If your supplier is based in the EU, we would recommend that you contact your supplier to find out whether the supplier has applied for authorisation, and whether you can benefit from this.
>
> If you source the substance directly from outside the EU, the duty to apply for authorisation would fall to you. However, we appreciate that this may be an unrealistic task. Please don’t hesitate to get back in touch with the helpdesk should you wish to discuss this further.
>
> I hope this helps.
>
> Kind regards,
>
> Laura
> ------------------------
> Laura McCabe
> REACH & CLP Helpdesk
> Chemicals Regulation Division
>
> HSE, Redgrave Court, Bootle, Merseyside L20 7HS
>
>
>
> Sent from my iPad
> _______________________________________________
> Alt-photo-process-list | altphotolist.org
>
>



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