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प्रश्न
Complete the process of iron rusting by filling the blanks. Suggest a way to prohibit the process.
The iron rust is formed due to........................... reaction. Different
regions on iron surface become anode and cathode.
Reaction on anode region :
`F_e(s) → Fe^(2+) (aq) +2e^-`
Reaction on anode region :
`O_2(g) + 4H^+(aq) +............................ → 2H_2 O (l) `
When Fe2+ ions migrate from anode region they react with ................... to form Fe3+ ions.
A reddish coloured hydrated oxide is formed from ............... ions. It is called rust.
`2Fe_(3+) (aq) + 4H_2O(l) → ................. + 6H_+(aq) `
A way to prevent rusting ..................................................................
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उत्तर
The iron rust is formed due to Electrochemical reaction. Different regions on iron surface become anode and cathode.
Reaction on anode region :
`F_e(s) → Fe^(2+) (aq) +2e^-`
Reaction on anode region :
`O_2(g) + 4H^+(aq) + 4 e- → 2H_2 O (l) `
When Fe2+ ions migrate from anode region they react with water to form Fe3+ ions.
A reddish coloured hydrated oxide is formed from Fe3+ ions. It is called rust.
`2Fe_(3+) (aq) + 4H_2O(l) → Fe_2O_3 . H_2O(s) + 6H_+(aq) `
A way to prevent rusting (Marks should be given for complete process and correct answers)
Prevention by colouring with acrylic paints, Zn plating, galvanizing, anodizing, alloying etc.) (Any one way of prevention expected.)
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संबंधित प्रश्न
Tinning : Tin : : Galvanizing : _________
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Mention two uses of the following metals and non-metals
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Electrolysis
Complete flow chart given below.
Write a molecular formula for rust.
Observe the following figure and write the answer of the question.
- Which process is shown in the figure?
- Explain the chemical reaction shown in the figure.
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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.
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| 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. |
- Name the anode and electrolyte used in this technique.
- How can we make aluminium articles made resistant to corrosion?
- Name the technique used to coat the aluminium articles.
