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प्रश्न
Corrosion of silver causes a black layer of _______.
विकल्प
Silver nitrate
silver oxide
silver sulphide
silver carbonate
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उत्तर
Corrosion of silver causes a black layer of silver sulphide.
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संबंधित प्रश्न
What is an alloy?
Tinning : Tin : : Galvanizing : _________
Explain why rusting of iron objects is faster in coastal areas than in deserts.
Explain why Iron sheets are coated with zinc during galvanization.
What type of chemical reaction is involved in the corrosion of iron?
Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
Name the metal which is used for galvanising iron.
State two conditions for the rusting of iron.
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Fill in the following blank with suitable word:
The process of depositing a thin layer of zinc on iron articles is called .............
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?
Bronze is an alloy of ______.
Name the metal which is a constituent of plant pigment?
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.
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 ..................................................................
Find the odd man out:
What are the adverse effects of corrosion?
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Give reason.
A wooden article should be polished.
Observe the following picture and answer the following questions:

- What is rust?
- Write the chemical formula of rust.
- Write the reaction of oxidation of iron at the anode.
- Write the reaction of oxidation of iron at the cathode.
- What is corrosion?
_______ forms a green colour in the water.
Stainless steel is an alloy of _______.
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
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.
State two conditions necessary for rusting of iron.
Copper objects lose their shine and form green coating of ____________.
Which among the following alloys contain mercury as one of its constituents?
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.

The substance not likely to contain CaCO3 is:
Generally, when metals are treated with mineral acids, hydrogen gas is liberated but when metals (except Mn and Mg), treated with HNO3, hydrogen is not liberated, why?
State whether the following statement is true or false:
Ships suffer a lot of damage though they are painted.
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Gold plated ornaments is the example of ______.
