A sewage pH=5, containing a small amount of NaCl and sodium sulfate, from the corrosion point of view should be used iron tube, aluminum tube or ceramic pipe?
Ceramic pipes are the best against corrosionFollowed by aluminum tubesThen the iron pipe
Acid waterThere are sodium particles in the waterIron pipes and sodium pipes are corrodedCeramic pipes should be used
The Al pipe is the iron tube againBecause the metal activity order table is: K, Ca, Na, Mg, Al, Zn, Fe, Sn, Pb (H), Cu, Hg,, Ag, Pt, AuAluminium is more iron than iron, so it is more active than iron, and PH=5 is acidThe activity of metals decreases gradually from strength to strengthSummary: 1. Only the metal placed in front of the H can displace the hydrogen in the acid2 only the metal in the front can displace the metal that is placed behind it from its salt solution
