Any chemical substance cheaper than AgNO3 but perform similar function, by which one can visually observe precipitations when chemical substance react with penetrated chlorides.
There are unlikely to be any alternatives which could be readily used. The only insoluble chloride salts (which is what you need if you want to have a visible marker) are those of silver and lead. Lead chloride would therefore also produce a white precipitate in the presence of soluble chlorides, but in the presence of portlandite you might also get a lead oxide precipitate, lead hydroxide (which is unstable) or more likely a basic lead carbonate. Lead oxide is red or yellow, lead hydroxide is off-white, as is basic lead carbonate. So, you wouldn't see a clear colour boundary.
- Badges
- Science topic