Question

A metal rod half immersed in water starts corroding at the bottom. Give reasons. 

 

Answer 1

A metal rod when partially dipped in water or dilute solution of salt; like Nacl and if solution is not agitated properly then the parts of the strip above and closely adjacent to the water line are more strongly aerated, because they have more strongly aerated, and have more supply of oxygen while remaining parts of rod which is immersed to greater depth have less supply of oxygen and these are poorly aerated and show lower oxygen concentration and hence a metal rodhalf immersed in water starts corroding at the bottom.