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प्रश्न
Fill in the following blanks with suitable words:
Tiffin boxes are electroplated with .............. but car bumpers are electroplated with ............... to protect them from rusting.
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उत्तर
Tiffin boxes are electroplated with tin but car bumpers are electroplated with chromium to protect them from rusting.
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संबंधित प्रश्न
Tinning : Tin : : Galvanizing : _________
Why do we apply paint on iron articles?
Give reasons:
Platinum, gold and silver are used to make jewellery.
Name five methods of preventing rusting of iron.
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.
In stainless steel alloy, iron metal is mixed with:
(a) Cu and Cr
(b) Cr and Ni
(c) Cr and Sn
(d) Cu and Ni
Brass is an alloy of:
(a) Cu and Sn
(b) Cu and Pb
(c) Pb and Sn
(d) Zn and Cu
Four metals P, Q, R and S are all obtained by the reduction of their oxides with carbon. Metal P is used to form a thin layer over the sheets of metal S to prevent its corrosion. Metal Q is used for electroplating tiffin boxes made of metal S whereas metal R is used in making car batteries. Metals Q and R form an alloy called solder. What are metals P, Q, R and S? How have you arrived at this conclusion?
No chemical reaction takes place when granules of a solid, A, are mixed with the powder of another solid, B. However when the mixture is heated, a reaction takes place between its components. One of the products, C, is a metal and settles down in the molten state while the other product, D, floats over it. It was observed that the reaction is highly exothermic.
(i) Based on the given information make an assumption about A and B and write a chemical equation for the chemical reaction indicating the conditions of reaction, physical state of reactants and products and thermal status of reaction.
(ii) Mention any two types of reactions under which above chemical reaction can be classified.
Give reason.
An iron article should be given a coat of paint
Give reason for the following:
A suspension of rust is basic in nature.
_______ forms a green colour in the water.
Stainless steel is an alloy of _______.
Bronze : _______ : : Stainless steel : Fe + Cr + C
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Draw a neat labelled diagram.
Anodizing
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.
- Write the reactions on anode and cathode.
The diagram shows the reaction between metal and dil. acid.
What is the reason for different behaviour of Mg in test tube B?
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
