Random memory

[pne]

In chemistry class one day, we watched a video about the noble gasses.

There was a narrator sitting on a big stone or something; several balloons were taped to the edge of the stone. He'd take off one at a time, explain which noble gas was inside, then tell us something about the properties of that gas. At the end, he'd let go of that balloon.

The most memorably bit was the one he described as a "lead balloon"—the gas in question was heavier than air, so instead of floating up into the sky the way the first ones did, it fell fairly quickly to the ground.

Comments

[robnorth.livejournal.com]

Although, to be fair, the British were trying to make the name conform to the general convention that metals' names end with "-ium". Apart from the metallic elements known in ancient times (e.g. lead, gold, copper) with equally ancient names, I think the only other metallic element with a name that ends only in "-um" (no "i") is platinum. (Although the Brits don't call that "platinium", IIRC....)

Metals in -um

[pne.livejournal.com]

The WP article that ubykhlives pointed to also mentions molybdenum and tantalum