Is that the 12 days of Christmas coming on?

Here is a photo of the coloured compounds I used for my Halloween themed chemical puzzle.  Did you spot the mistake I made in the Halloween poem?

Iron (III) thiocyanate (not iron (II) thiocyanate) is often used as ‘fake blood’.  In the photo above it’s the dark red compound formed where the colourless potassium thiocyanate and orange iron (III) chloride solutions meet.

Here’s another photo of iron (III) thiocyanate in solution at three different concentrations:

Iron (III) thiocyanate

The red colour changes quite a bit!

In my last post I asked what a hygroscopic material was; well it’s one that absorbs water from the atmosphere.  It’s a problem if you try to keep a sample of a hygroscopic compound like lithium chloride, LiCl.  It always gets wet and starts dissolving in the water it absorbs from the atmosphere.  The trick is to keep it in a dessicator.

What is a dessicator?

Oh, and the displacement reaction for the wolf’s head in the last post is:

copper + silver nitrate –> silver + copper nitrate

The crystals you see hanging from the wolf’s jaw are silver crystals and of course, werewolves are supposed to be repelled by silver.

Well, Christmas is a coming, so here’s a doodle using copper in a Christmas theme:Exif_JPEG_PICTURE

So green Santa it is, sporting a suit the same colour as copper (II) chloride.

Not all copper compounds are green.  What colour are copper (II) nitrate and copper (II) sulfate?


Horrorchemie ?

In theory, lithium chloride, lithium bromide and lithium iodide would all be predicted to occur as white crystalline solids. However, when re-crystallising lithium chloride it proved to be hygroscopic.

Here’s a picture of some lithium chloride (I don’t have lithium bromide or lithium iodide):

What does hygroscopic mean?

And for fun, here are some “horrorchemie” photos illustrating the Halloween poem:


Can you identify the coloured chemical compounds? Or the displacement reaction for the wolf?