What is the effect of salty water on rusting?

• A. It speeds rusting
• B. It has no effect on rusting
• C. It stops rusting
• D. It makes rusting unpredictable

Answer: (B)

Rusting is an electrochemical process that needs water and oxygen. When water contains salt, it becomes a better electrolyte because the dissolved ions increase the solution’s conductivity. This makes it easier for the electrons to flow between the iron and the oxygen-reducing reactions, speeding up the corrosion process. Additionally, chloride ions from the salt can attack any protective oxide layer on the iron, promoting rust at cracks and edges. So salty water speeds rusting, not leave it unchanged or stop it.