Australia's Science Forum

My solid lead nitrate has parts of it yellow, has this oxidized??? Can I still use it??????????

Sounds like it's been used for the Lead Nitrate/Potassium Iodide experiment and somebody has contaminated your solution. Bright yellow is Lead Iodide. Sorry!

If its the dry chemical, you could just dispose of the yellow stuff. Just had a look at mine and there are two rusty coloured crystals. Not sure if it is contaminated or gone off (if it does go off).

Thank you Smiley & Dime, its bright yellow, no good. Lucky their was only a little left. See the price on a new one from Serrata 134.90 for AR or $44.?? for LR. Its a crime.

Yeah, just doing an order for some chemicals from Serrata: Potassium Iodide $71.99 for 500g....a bit XXXXie eh! not to mention salt and metho! Glad I'm not paying!

Labbie,
just go for the cheap one!! We don't use AR because for the purpose of school education we do not need to be that accurate. The LR is good enough
We bought a 3kg container this year. Somehow we have 'lost' a lot of copper sulfate the last 2 years. I usually just recyle it but not that much seems to be coming back anymore :(
Rosalie

Sorry - ignore the reference to copper sulfate... my brain was still in the last thread I was reading!!

We only buy the LR (laborarory reagent). It is pure enought for all our practicals.
Lada

we only buy and use the LR stuff, couldn't afford to pay for the dear stuff.

Hi All,

Small amounts of absorbed water can also send the Lead Nitrate a little yellow.

Cheers,

Robb.....

OK I'm confused . Was at a PL day last week and I spotted 0.1M lead nitrate Droppers in the prep room of the school we were at . They had a green Detra sticker . I commented that it was wrong and that it should be Orange .

So we looked it up in CSIS .....(yes I know CSIS is out of date but that is what we Public schools have to use as a guide .)
Sure enough it said 7-12 ( green dot) for solid .

Search result for: lead(II) nitrate

Table showing details for lead(II) nitrate
Chemical
Category & User Codes
DG Class
DG PG
UN CAS No
Guidance notes
lead(II) nitrate
lead nitrate*
7-12
1
2
-
-
5
-
-
5.1/6.1

DHS

CW

Hazardous Chemical II 1469
10099-74-8 Highly toxic by all routes of exposure; cumulative poison.
Use eye and skin protection where splashes can occur. Use in a fume cupboard if practicable; otherwise use small quantities (< 10 mL or g) in a well-ventilated area.
Forms explosive mixtures with combustible materials (such as sulfur, phosphorus and metal powders) and with organic compounds.
Can be used to generate nitrogen dioxide by heating the solid; carry out this reaction on a small scale (<1 g) since nitrogen dioxide is highly toxic, as are any particles of lead salts released. Students should only carry out experiments with this salt under close supervision. Typically, student use should be limited to 5 mL of 0.1 M per activity per student/group activity. Used to test for anions, e.g. produces a bright yellow precipitate of lead iodide with sodium or potassium iodide.
Q-Stores

39
See also HEAVY METAL COMPOUNDS and OXIDANTS.

so we looked at the solution .
It had solution <1% 7-12 ( green sticker)

Note: An asterisk(*) flags the name by which the chemical is listed on the Chem Watch MSDS database

Search result for: lead(II) nitrate

Table showing details for lead(II) nitrate
Chemical
Category & User Codes
DG Class
DG PG
UN CAS No
Guidance notes
lead(II) nitrate
. . . solution <1%
7-12
1
2
-
-
5
-
-
NR

Not Hazardous -
-
10099-74-8 Not Hazardous according to Worksafe criteria. Should not be ingested.
39

Now 0.1M works out to be 3.3%

There was no mention of solutions >1% .....so what is the user group ????......or are we not allowed to make solutions stronger than 1% .
But then back up in solids it did mention 0.1M
Curious how you all interpret this .

This is according to the Risk Assess program if you are using it, that is what you are required to follow.


lead(II) nitrate, solid
Class: 5.1/6.1 PG: II Users: Tch Training: 1,2,5* CAS: 10099-74-8 UN: 1469
GHS data:
DANGER
Oxidizing Corrosive Harmful Health hazard Environmentally damaging May intensify fire; oxidizer
Harmful if swallowed
Causes serious eye damage
Harmful if inhaled
May damage fertility or the unborn child
May damage organs through prolonged or repeated exposure
Very toxic to aquatic life
Potential hazards
HIGHLY TOXIC; CUMULATIVE POISON; MAY DAMAGE FERTILITY AND THE UNBORN CHILD. Forms explosive mixtures with combustible materials (such as sulfur, phosphorus and metal powders) and with organic compounds.

Standard handling procedures
Wash hands thoroughly after using lead salts. Should not be handled by pregnant women. Women of reproductive age should avoid handling the chemical. Can be used to generate nitrogen dioxide by heating the solid; carry out this reaction on a small scale (1 g) in a fume cupboard since nitrogen dioxide is highly toxic, as are any particles of lead salts released.



lead(II) nitrate 0.003-0.03 M (0.1-1% wt/wt)
Class: nc PG: none Users: 11-12 Training: 1,2,5* CAS: 10099-74-8[/b]
GHS data:
DANGER
Harmful Environmentally damaging May damage fertility or the unborn child
Harmful to aquatic life
Potential hazards
HIGHLY TOXIC; CUMULATIVE POISON; MAY DAMAGE FERTILITY AND THE UNBORN CHILD.

Standard handling procedures
Wash hands thoroughly after using lead salts. Should not be handled by pregnant women. Women of reproductive age should avoid handling the chemical.


lead(II) nitrate <0.003 M (<0.1% wt/wt)
Pb(NO3)2(aq)lead(II) nitrate <0.003 M (<0.1% wt/wt)
Class: nc PG: none Users: 7-12* Training: 1,2,5* CAS: 10099-74-8
GHS data: Not classified as a hazardous chemical.
Potential hazards
Pure chemical is a cumulative poison and may damage fertility or the unborn child

Standard handling procedures
Wash hands thoroughly after using lead salts.

This is always my example I use when talking about how old, and out of date CSIS is. It is a crime that students in DET schools are being exposed to a chemical that has now been found to be so toxic. Not to mention the poor labbies that handle the solid. It really is time the DET caught up with the real world.

Merilyn1 wrote: ↑02 Jul 2019, 07:51 This is always my example I use when talking about how old, and out of date CSIS is. It is a crime that students in DET schools are being exposed to a chemical that has now been found to be so toxic. Not to mention the poor labbies that handle the solid. It really is time the DET caught up with the real world.

Hear Hear! I wonder what the legal system would have to say, if they knew...

I do wonder. Would it be feasible if a few, ie every, labbie in DET schools started contacting their WHS people? Lead is the real stand out, but how many other chemicals are in the same boat? Someone needs to be checking and notifying their workers.
Sometime in the future we may be reading about this in the news...

I totally get that its wrong and out of date but, my question was how have DET schools been labelling their Lead nitrate in the last 21 years ?

How have DET Labbies interpreted the CSIS info on it and used it to label their Lead Nitrate solutions ?

Sorry Richard - seems like we all went off on a rant. If, according to CSIS, the solid is 7-12 and the solution of <1% is also 7-12, wouldn't everything in between be 7-12? That was the path I took many, many moons ago when I had to use CSIS.
I'm no good with the maths, but Riskassess has 0.003 to 0.03M as equivalent to 0.1-1%.
Although, given the discussion, for the safety of students, I would be labelling 0.003 to 0.03M as 11-12 and <0.003M as 7-12, in accordance with Riskassess guidelines. I'd be telling management to jam CSIS in their chem store!

Cobalt Chloride and Nickel Chloride are another two that concentrations have been drastically reduced. I think if I was in a DET school I would be pushing for HT to get Risk Assess, I know a lot in our area are using it. Not just our safety but everybody concerned it's kept up to date, any questions they are only a email away and reply the same day. Couldn't get better service for the little amount $250.

Teachers get used to it.

Read the SDS. It's what I always do, just to double check, it's up to us to protect our own health and that of the students.. I have Risk Assess too. It has saved me sooo much time labelling.

Sorry to resurrect an old thread, but I just started as the Lab Manager at my school, and the prep room cupboards are filled with lead nitrate dropper bottles for student use for precipitate and replacement reaction pracs, but they're all either 1M or 0.5M, both of which are big no nos according to RiskAssess. The school just started using RiskAsses and I'm very safety conscious so I've taken it upon myself to come up with some alternatives.

For the short-term I've provided 0.05M Silver Nitrate for the labs that require precipitates and for the replacement reaction with KI. It's way more expensive than Lead Nitrate, of course, but it works and is safe for students 7-12 according to RiskAssess. Just make sure students wear gloves and lab coats as Silver Nitrate does stain your skin!

But my big question is what everyone else is doing about Lead Nitrate being used in pracs in their school? Does making a <0.003M solution (let's say a 0.001M solution since that's easy) still produce the same visual results that teachers want their students to be able to see?