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प्रश्न
_______ is an alloy made from iron, carbon and chromium.
विकल्प
brass
bronze
stainless steel
amalgam
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उत्तर
Stainless steel is an alloy made from iron, carbon and chromium.
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संबंधित प्रश्न
Tinning : Tin : : Galvanizing : _________
Give reasons:
Platinum, gold and silver are used to make jewellery.
The corrosion of copper produces a ______ coating of basic copper carbonate on its surface.
Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
Name five methods of preventing rusting of iron.
Name an alloy of copper. State its chemical composition and any one use.
Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
Name a common metal which is highly resistant to corrosion.
A metal X which is resistant to corrosion is produced by the electrolysis of its molten oxide whereas another metal Y which is also resistant to corrosion is produced by the reduction of its oxide with carbon. Metal X can be used in powder form in thermite welding whereas metal Y is used in making cathodes of ordinary dry cells.
- Name the metals X and Y.
- Which of the two metals is more reactive: X or Y?
- Name one ore or metal X. Also write its chemical formula.
- Name one ore of metal Y. Also write its chemical formula.
- Name one alloy of metal X and one alloy of metal Y.
Name the metal which is a constituent of plant pigment?
Explain how the activity series accounts for each of the following:
tendency to corrosion
Compare roasting and calcination.
Observe the following picture a write down the chemical reaction with the explanation.
Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
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 ..................................................................
Identify the process shown in the diagram and explain it in short
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give reason.
Copper and brass utensils should be tinned.
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
To prevent corrosion of iron and steel _______ method is used.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Find the correlation:
Bronze : ______ :: Tin : Cu+Zn.
Find the odd one out and give its explanation.
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
Write scientific reason.
Coins are made from metals and alloys.
Draw a neat labelled diagram.
Electrolysis
Draw a neat labelled diagram.
Anodizing
Write a molecular formula for rust.
Observe the following diagram and give answers.
- Name this method of prevention of corrosion.
- For prevention of which metal this method is used?
- What is used as anode in this method?
Observe the following diagram and write answers.
- Name the method.
- Explain the method.
- Give two examples of this method.
State two conditions necessary for rusting of iron.
The diagram shows the reaction between metal and dil. acid.
What is the reason for different behaviour of Mg in test tube B?
Gold plated ornaments is the example of ______.
Explain the chemical reactions in rusting of iron.
| 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.
In ______ process a layer of molten tin is deposited on metals.
