RE: are unadorned brackets always "concentration"?

These examples do indeed indicate the counterion. This group would have a superscript charge if on their own but in these examples they are followed by anions which balance the charge. A concentration square bracket would have a space after it.

Elaine

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From: Neil Soiffer<mailto:soiffer@alum.mit.edu>
Sent: 27 June 2022 08:07
To: Chemistry CG<mailto:public-chem-web-pub@w3.org>
Subject: are unadorned brackets always "concentration"?


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I thought that if there are unadorned square brackets (i.e., no sub or superscripts), then that means "concentration of...". However, on this wikipedia page<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FSalt_metathesis_reaction%23Counterion_exchange&data=05%7C01%7Ce.a.moore%40open.ac.uk%7C3735dc752d434d9c7f0408da580bc3a9%7C0e2ed45596af4100bed3a8e5fd981685%7C0%7C0%7C637919104795553835%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=cdPDX4A6GotcSPwAkThx%2FpCOeLTRmHdJh9fvzkwgDqA%3D&reserved=0>, there are lots of examples of unadorned brackets. My knowledge of chemistry is limited, but to my eyes, these uses of brackets are not meant to be "concentration".

Are they just grouping symbols to indicate the counterion? If so, how do I distinguish between their use as grouping symbols and their use as concentration?

Thanks,

    Neil