Physical and Chemical Changes — Science STD 7 — Question
Gujarat BoardEnglish MediumSTD 7SciencePhysical and Chemical Changes1 Mark
MCQ
What conditions are required for rusting to take place?
A
Water only
B
Oxygen only
✓
Water and oxygen
D
Water and carbon dioxide
✓
Answer
Correct option: C.
Water and oxygen
Rust is a general term for a series of iron oxides, usually, red oxides, formed by the reaction of iron with oxygen in the presence of water or air moisture. It is the common term for corrosion of iron and its alloys, such as steel. Both water and oxygen are required to form rust from metal iron.
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