Not all spontaneous redox reactions produce wonderful results. Corrosion is an example of a spontaneous redox process that has negative effects. What happens in the corrosion of a metal such as iron? What must be present for the corrosion of iron to take place? How can moisture and salt increase the severity of corrosion? Explain how the following protect metals from corrosion: a . paint b. durable oxide coatings c . galvanizing d. sacrificial metal e. alloying f . cathodic protection

Interpretation:

Corrosion as an example of a spontaneous redox process that has negative effects is given. The concept of corrosion and its prevention using given methods is to be stated.

Concept introduction:

Corrosion is a process that involves the deterioration of metal surface in the process of moisture and oxygen.

Various methods like, painting, galvanizing, alloying, durable oxide coatings, sacrificial metal method, cathodic protection method can be used for the protection of metal from corrosion.

To determine: The protection of metals by using paint.

Paint prevents the contact of moisture and air with the metal, which reduces the chances of corrosion.

Corrosion of metal enhances in the presence of moisture and oxygen. Therefore, after applying paint over the metal surface, the chances of their attack over metal surface decreases. And this prevents the metal from corrosion.

Metals oxidize during the process of corrosion.

Corrosion involves the process in which metals attain their natural oxidation state. It is a type of redox reaction where metal is oxidized in the presence of oxygen.

The main requirements for corrosion of iron to occur are oxygen and water.

Iron undergoes oxidation in aqueous solution,

2Fe→2Fe2++4e-

Oxygen dissolved in water undergoes reduction,

O2+2H2O+4e-→4

Interpretation:

Corrosion as an example of a spontaneous redox process that has negative effects is given. The concept of corrosion and its prevention using given methods is to be stated.

Concept introduction:

Corrosion is a process that involves the deterioration of metal surface in the process of moisture and oxygen.

Various methods like, painting, galvanizing, alloying, durable oxide coatings, sacrificial metal method, cathodic protection method can be used for the protection of metal from corrosion.

To determine: The protection of metals by using durable oxide coatings.

Interpretation:

Corrosion as an example of a spontaneous redox process that has negative effects is given. The concept of corrosion and its prevention using given methods is to be stated.

Concept introduction:

Corrosion is a process that involves the deterioration of metal surface in the process of moisture and oxygen.

Various methods like, painting, galvanizing, alloying, durable oxide coatings, sacrificial metal method, cathodic protection method can be used for the protection of metal from corrosion.

To determine: The protection of metals by using galvanizing method.

Interpretation:

Corrosion as an example of a spontaneous redox process that has negative effects is given. The concept of corrosion and its prevention using given methods is to be stated.

Concept introduction:

Corrosion is a process that involves the deterioration of metal surface in the process of moisture and oxygen.

Various methods like, painting, galvanizing, alloying, durable oxide coatings, sacrificial metal method, cathodic protection method can be used for the protection of metal from corrosion.

To determine: The protection of metals by using the sacrificial metal method.

Interpretation:

Corrosion as an example of a spontaneous redox process that has negative effects is given. The concept of corrosion and its prevention using given methods is to be stated.

Concept introduction:

Corrosion is a process that involves the deterioration of metal surface in the process of moisture and oxygen.

Various methods like, painting, galvanizing, alloying, durable oxide coatings, sacrificial metal method, cathodic protection method can be used for the protection of metal from corrosion.

To determine: The protection of metals by using alloying method.

Interpretation:

Corrosion as an example of a spontaneous redox process that has negative effects is given. The concept of corrosion and its prevention using given methods is to be stated.

Concept introduction:

Corrosion is a process that involves the deterioration of metal surface in the process of moisture and oxygen.

Various methods like, painting, galvanizing, alloying, durable oxide coatings, sacrificial metal method, cathodic protection method can be used for the protection of metal from corrosion.

To determine: The protection of metals by using cathodic protection method.