हिंदी

Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.

Advertisements
Advertisements

प्रश्न

Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.

स्पष्ट कीजिए
Advertisements

उत्तर

Galvanisation involves coating iron objects with a layer of zinc to prevent oxygen and moisture from reaching the iron underneath. Because zinc is more reactive than iron, it loses electrons more easily. If the zinc layer is broken, a phenomenon called sacrificial protection occurs. The zinc preferentially undergoes oxidation (corrosion) before the iron, thereby protecting the underlying iron article from rusting.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Metals and Non-metals - Exercise 3 [पृष्ठ २३३]

APPEARS IN

लखमीर सिंग Chemistry Part 2 [English] Class 10
अध्याय 3 Metals and Non-metals
Exercise 3 | Q 59. (d) | पृष्ठ २३३

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

What is an alloy?


Give reasons:

Platinum, gold and silver are used to make jewellery.


______ and ______ are necessary for the rusting of iron.


Give the constituents of brass.


Name five methods of preventing rusting of iron.


What are the special properties of stainless steel?


Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?


Identify the process shown in the diagram and explain it in short


Answer the following question.
a) What is meant by corrosion?
b) Write names of any two methods of prevention of corrosion.
c) In which method, metal like copper, aluminium are coated with a thin layer of their oxides by means of electrolysis.
d) Explain this method with diagram.


State whether the statement given below is true or false. If false write the correct statement.

Graphite is a lustrous non-metal which conducts electricity.


When one of the metals in an alloy is mercury the alloy is called _______.


Match the columns.

Group A Group B
1) Electroplating a) Pressure cooker
2) Anodising b) Silver plated spoons
  c) Coating of tin on copper
  d) Coating of Zinc on iron

Write the name.

Method used to present corrosion of copper.


Observe the following figure and write the answer of the question.

  1. Which process is shown in the figure?
  2. Explain the chemical reaction shown in the figure.
  3. Write the reactions on anode and cathode.

Give solutions by giving examples of corrosion?


Copper objects lose their shine and form green coating of ____________.


Generally, when metals are treated with mineral acids, hydrogen gas is liberated but when metals (except Mn and Mg), treated with HNO3, hydrogen is not liberated, why?


Explain the following:

Lime water turns milky on passing carbon dioxide gas into it.


Give an example of a chemical reaction for the following situation:

Sound is produced


A process of forming a thick oxide of aluminium when aluminium is exposed to air. This coat makes it resistant to corrosion. Resistance can be improved by making a layer of oxide thinker. In this technique, the aluminium article is the anode, and the electrolyte is sulphuric acid. The anode reaction results in the formation of a black-coloured film of aluminium oxide on the anode. By putting appropriate dyes in the electrolytic solution, both coloured surface with the decorative finish is achieved. Kitchen articles like anodised such as pressure cookers, pans and frames of sliding windows are applications of this technique.
  1. Name the anode and electrolyte used in this technique.
  2. How can we make aluminium articles made resistant to corrosion?
  3. Name the technique used to coat the aluminium articles.

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×