Advertisements
Advertisements
Question
Why do we apply paint on iron articles?
Advertisements
Solution 1
Iron articles are painted because it prevents them from rusting. When painted, the contact of iron articles with moisture and air is cut off. Hence, rusting is prevented.
Solution 2
Iron articles are painted to prevent them from rusting. When left unpainted, the metal surface comes into contact with atmospheric oxygen, and in the presence of moisture, it becomes iron (III) oxide. But if painted, the surface does not come into contact with moisture or air, thus preventing rust.
APPEARS IN
RELATED QUESTIONS
Which metals do not corrode easily?
What is anodising? Give its applications.
What type of chemical reaction is involved in the corrosion of iron?
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Why is an iron grill painted frequently?
Give the constituents and one use of brass.
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
Name an alloy of copper. State its chemical composition and any one use.
Name the metal which is a constituent of blood pigment?
State under what conditions corrosion is faster ?
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
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.
Give a reason why rust turns moist red litmus blue.
_______ is an alloy made from iron, carbon and chromium.
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
When one of the metals in an alloy is mercury the alloy is called _______.
Marble’s popularity began in ancient Rome and Greece, where white and off-white marble were used to construct a variety of structures, from hand-held sculptures to massive pillars and buildings.
The substance not likely to contain CaCO3 is:
Identify the correct statement from the following:
In ______ process a layer of molten tin is deposited on metals.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
