Corrosion and Rancidity Class 10th;Difference between Corrosion and Rancidity

Corrosion and Rancidity Class 10th:

The reaction of metals with air or oxygen or moisture, acids etc present around it is called corrosion. Corrosion in case of iron metal is called Rusting. Oxidation of oils or fats in food is called Rancidity. These processes are unwanted and can be prevented by avoiding contact with air or by painting.

Corrosion:

• It is a natural process.
• It is the process in which metals deteriorate gradually by the reaction of oxygen and water and forming an oxide layer on the surface of the metal.
• Due to corrosion pure metal is converted into an undesirable substance.
• In the case of iron, it is called rusting.
• When a piece of iron is left out in moist air, it slowly changes into a dull brittle brown substance called rust (Fe₂O₃.xH₂O).
• The formation of rust on the surface of iron is called the rusting of iron.
• Chemical reaction:
• 4Fe       +       O₂       +2xH₂O                  →      2Fe2O₃.xH₂O (Rust)                                                                                       Iron          Oxygen      water                           Hydrated Iron (III) Oxide

• 

• Rancidity:

  • The term ‘rancidity’ means a condition in which food has become undesirable.
  • It is often used to describe the oxygen content of oils.
  • It is a term used to describe the oxygen damage in food.
  • When oxygen molecules interact with the oil and food, the normal structure of the food is disturbed, resulting in a change in odor and taste, and it is not recommended for consumption.

  For example, An example of rancidity is when a chips packet is exposed to atmospheric air which results in a change in taste and odor.

  

  FAQ

• Q.(1)Explain the following term with one example: Rancidity.

  Solution
   

  Rancidity- It refers to the oxidation of fats and oils in food that is kept for a long time. It gives foul smell and bad taste to food and causes stomach infection upon consumption.

  Prevention:
  (i) Use of air-tight containers
  (ii) Packaging with nitrogen
  (iii) Refrigeration
  (iv) Addition of antioxidants or preservatives

  Q.(2)Explain the following term with one example: Corrosion.

  Solution

   

  Corrosion- The gradual deterioration of a material, usually a metal, by the action of moisture, air or other chemicals in the surrounding environment is called corrosion.

  Corrosion of iron is called rusting. Green coating on copper articles and black coating on silver ornaments are other examples of corrosion.

  • 4Fe       +       O₂       +2xH₂O                  →      2Fe2O₃.xH₂O (Rust)                                                                                       Iron          Oxygen      water                           Hydrated Iron (III) Oxide                                                                                  

  Q.(3) What is rancidity class 10?

  Ans:- When fats and oils stay in open for long, they get oxidized and become rancid (old and stale), and their smell and taste change. This process is known as rancidity. It is also known as vikiritygandhita in Hindi.

  Q.(4)What is called corrosion?

  Ans.:-Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engineering is the field dedicated to controlling and preventing corrosion.

  4Fe       +       O₂       +2xH₂O                  →      2Fe2O₃.xH₂O (Rust)                                                                                                                     

  Q.(5)What is corrosion class 10 with examples?

  Ans.:-Corrosion is the process by which a metal surface is attacked by a certain substance such as air or water. The most common occurence of corrosion is the rusting of iron by air and moisture to form a reddish-brown layerof triferric tetraoxide(Fe3O4)

  Q.(6)What is oxidation and rancidity?

  Ans.:-Food turns rancid when the fats and oils within them get oxidized and the taste and smell of the food changes. Oxidation of fats generates highly reactive molecules in the rancid food which is responsible for the unpleasant odour and flavour. These chemical reactions also reduce the nutrition of the food.