determine the molality and mole fraction of concentrated aqueous hcl, which is 12.0 m and has a density of 1.19 g/ml.

You need to divided twenty four by a dozen them by the temperature it is getting cook by

They are all solids.

High-energy and unstable.

Remember that rust prevented by placing a sacrificial electrode in electrical contact with the iron. the sacrificial electrode must be composed of a metal that  oxidizes  more easily than iron (that is, it must be below iron in table 18.1).