Alkali

In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Some authors also define an alkali as a base that dissolves in water. A solution of a soluble base has a pH greater than 7. The adjective alkaline is commonly used in English as a synonym for base, especially for soluble bases. This broad use of the term is likely to have come about because alkalis were the first bases known to obey the Arrhenius definition of a base and are still among the more common bases.

Alkali

The word "alkali" is derived from Arabic al qalīy (or alkali), meaning the calcined ashes (see calcination), referring to the original source of alkaline substances. A water-extract of burned plant ashes, called potash and composed mostly of potassium carbonate, was mildly basic. After heating this substance with calcium hydroxide (slaked lime), a far more strongly basic substance known as caustic potash (potassium hydroxide) was produced. Caustic potash was traditionally used in conjunction with animal fats to produce soft soaps, one of the caustic processes that rendered soaps from fats in the process of saponification, known since antiquity. Plant potash lent the name to the element potassium, which was first derived from caustic potash, and also gave potassium its chemical symbol K (cf German Kalium), which ultimately derives from alkali.

A pot of jam

Henry Farrell writes, apropos of an article in the Guardian:

There's a bit of language play there that may escape non-UK/Irish readers. "Jammy" in "jammy first-timers" means 'possessed of undeserved luck.' It's almost never used afaik except as part of the phrase "jammy bastard."

I was just thinking the other day of this lyric from the musical "Sweet Charity":

All I can say is "Wow-ee!"
Look-a where I am.
Tonight I landed, pow!
Right in a pot of jam.
What a set up! Holy cow!
They'd never believe it,
If my friends could see me now!

In particular, I was thinking that I had never heard the expression "land in a pot of jam" to mean lucky in any other context. (The lyricist, Dorothy Fields, was an American, not a Brit.) Perhaps there's some connection.