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Preparation of SnCl4 Without Using Elemental Chlorine

SnCl4 (tin tetrachloride, tin IV chloride) can be prepared by direct union of chlorine with tin or with anhydrous tin II chloride. The use of toxic chlorine gas at high temperature makes this a potentially hazardous enterprise. But SnCl4 can also be prepared by pyrolysis of potassium hexachlorostannate (K2SnCl6). This post presents a first preparation […]


Preparation of Potassium Hexachloroantimonate (KSbCl6)

In a previous post I pointed to the existence of hexachlorostannates and antimonates and how these compounds can be used to separate tin and antimony. But while the preparation of hexachlorostannates using thermal crystallisation is fairly straightforward, I hadn’t until recently been able to isolate KSbCl6. Hexachloroantimanate salts can be prepared by combining antimony pentachloride […]


Hexachlorostannate: the Separation of Tin and Antimony

Tin (Sn) and antimony (Sb), despite belonging to different groups, show remarkable similarities in their chemistries and as a result are notoriously difficult to separate. Years ago I stumbled on a method almost inadvertently, which I will demonstrate here. 16.5 g of pewter (from an old beer tankard) was cut off and slightly cleaned up […]


Gadolinite: a qualitative analysis

In a previous post I showcased my Gadolinite-Y samples and a few weeks ago it was time to take apart a small, less attractive sample from the same batch. To that effect some 10 g of mineral was cut off and ground up. It soon became clear that beige Pegmatite particles were present in the […]


Density of solid objects: Archimedes’ little secret

I remain genuinely a little baffled by the number of amateur scientists who don’t seem to know about this little trick that makes Archimedes based density measurements of solid objects such a jiffy. Most of the Tinkerweb’s Archimedes guides remain oddly shtum about it too. Here’s how it’s done, using a lemon (why not?) I […]


Reverse Laminar Flow

Watch reverse laminar flow in reverse, from about 2’12”: Beautiful!


Gadolinite-Y and White Cloud Pegmatite: some samples

Here are some samples of the rare mineral Y-Gadolinite (sometimes known as Ytterbite) with White Cloud Pegmatite: Below, detail of the larger specimen: the near-black, glassy Gadolinite can clearly be seen. The samples were kindly donated to me by the University of New Orleans, and originate from the South Platte district, Jefferson Co., Colorado (USA). […]


Rare-Earth Metal Long Term Air Exposure Test

Rarely does one get to see a collection of Rare Earth metals (better named as Lanthanides, since as they’ve been shown not to be as rare as once believed) in one place as in the photo below. (Source, see below) Even rarer is a comprehensive study of the corrosion rate of these metals in room […]


Terbium dissolving in hydrochloric acid

Here’s another thing you don’t get to see any day of the week soon: pieces of the lanthanide element Terbium metal (Z = 65) dissolving in hydrochloric acid (HCl): Acid strength was 1.0 M. The very vigorous evolution of hydrogen gas (H2) at this relatively low acid concentration illustrates the strongly electropositive character of the […]


Pressurising Classical Chemistry?

ScienceDaily. Dec. 19, 2013 — All good research breaks new ground, but rarely does the research unearth truths that challenge the foundation of a science. That’s what Artem R. Oganov has done, and the professor of theoretical crystallography in the Department of Geosciences will have his work published in the Dec. 20, 2013 issue of […]