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प्रश्न
What is rust ?
उत्तर १
Rust: Rust is hydrated ferric oxide (Fe2O3 . x* H2O), which forms a brownish red coating over iron. (* x can be any number.)
उत्तर २
The hydrated oxide of iron formed when iron comes in contact with moist air is called rust. This rust is brownish flaky residue and easily crumbles from the metal surface.
4Fe + 3O2 → 2Fe2O3
Iron Oxygen Ferric oxide
संबंधित प्रश्न
What do you observe when Magnesium is heated and then tested with moist blue and red litmus – paper?
State at least two ways of prevent rusting.
Fill in the blank by choosing the correct word from the given list.
List: oxygen, carbonic, suIphur dioxide gas, precipitation, helium
____________ gas can cause acid rain.
Write ‘True’ or ‘False’ in front of following statement.
Nitrogen is a gaseous non-metal essential for respiration.
State how nitrogen is utilised by plants for their growth. Give a reason why nitrogen is used in flushing food packages.
In the laboratory preparation of oxygen from hydrogen peroxide answer the following:
Draw a neat labelled diagram for the method used in the above preparation.
In the laboratory preparation of oxygen from hydrogen peroxide answer the following:
State the method of collection of the oxygen gas giving reasons.
Give the main experimental points only to demonstrate that magnesium.
Name the following:
The pollutant which combines with water vapour to give sulphuric acid – a product of acid rain.
What is meant by burning?
