[Maupa]

Hello
First of all I am sorry about my lack of knowledge of chemistry and its vocabulary. I am an artist and for my project I need selection of minerals and chemicals in its pure form, some of which are not easy to get hands on e.g. phosphorus, nitrogen, potassium, arsenic (7mg) etc. Where can I order small amounts of chemicals? Can anyone help?
Eva

[Arkcon]

So you need some minerals, you can get those at a rock show.  People mine and trade/sell those at these shows, for decorative purposes like yours.  Pure chemicals, now that's a little harder, but if they're purely decorative, they may be there too.  The substances you've listed are pure elements, and although they are chemicals, aren't really minerals.  That said, tiny amounts of pure elements are often for sale for collectors like you.  Elemental phosphorus can be a little dangerous, and potassium more so, but if sealed away from hands, probably no worse than arsenic.  But nitrogen?  You do know that's 4/5 of the air around you, right?  So what did you want to do with it?  If the stuff around you is inadequate for your application, nothing you can buy will really cut either.

[billnotgatez]

 Artist Ceramic supply houses may have what you need.
Many minerals are used in glazing.

[typhoon2028]

Why do you need arsenic?

[Borek]

Why do you need arsenic?

To get rid of competition?

Seriously, 7 mg won't be enough to kill anyone, unless converted to some more potent compound. As trioxide it may kill even several peple.

[billnotgatez]

Phosphorus, nitrogen, potassium, and arsenic are all elements. Many elements form compounds with other elements. Some elements are hard to store in there elemental form because they are highly reactive with other elements like the oxygen in the air. Other elements or compounds are hard to keep because they seep out or eat away the common containers used for storage.
So if you have more to your list please post it and we will try to give you the background on each. Remember that the much the same can be found on the web by looking at items already posted on places like Wikipedia. Also if you search this forum you will find several posts involving people who collect elements and what they had to do to keep them.

Phosphorus is fairly reactive
Nitrogen is a gas that is about 80 percent of the air
Potassium is very reactive in the presence of oxygen so it is stored in a special way
Arsenic is a poison which should be stored so as not to harm anyone.

[pantone159]

You can get element samples here http://www.elementsales.com/ although they will not ship alkali metals (e.g. potassium), there are other suppliers as well.