Physical and Chemical Changes — Science STD 7 — Question
Gujarat BoardEnglish MediumSTD 7SciencePhysical and Chemical Changes1 Mark
MCQ
Rusting can be prevented by:
A
Coating the object with paint
B
Coating the object with grease
C
Galvanizing
✓
All of the above
✓
Answer
Correct option: D.
All of the above
Hint: A red$-$colored coat formed on iron by the reaction of iron with oxygen in presence of air is called rust. Explanation:
Rusting can be prevented by various methods.
$1.$ Coating the object with paint or grease can prevent rusting. The layer of paint and grease prevents the reaction of iron with air.
$2.$ Galvanization is the best method to prevent rusting. To protect the iron from rusting it is coated with zinc because zinc possesses a higher negative reduction potential than $Fe$ so zinc will oxidized before iron and protects iron from getting oxidized.
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