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प्रश्न
What is rust?
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उत्तर
A certain type of reddish coloured solid layer collects on iron surface. This layer is called ‘rust’.
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संबंधित प्रश्न
Why do we apply paint on iron articles?
Give reasons:
Platinum, gold and silver are used to make jewellery.
Choose the correct answer from the options given below:
Heating an ore in a limited supply of air or in the absence of air at a temperature just below its melting point is known as
A. Smelting
B. Ore-dressing
C. Calcination
D. Bessemerisation
The chemical reaction involved in the corrosion of iron metal is that of ______.
What is meant by galvanisation? Why is it done?
Explain why, iron sheets are coated with zinc.
Fill in the following blank with suitable word:
The process of depositing a thin layer of zinc on iron articles is called .............
Explain why, through 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.
What are the constituents of stainless steel?
Name a common metal which is highly resistant to corrosion.
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?
Name the metal which is a constituent of plant pigment?
Explain how the activity series accounts for each of the following:
tendency to corrosion
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.
Identify the process shown in the diagram and explain it in short
Find the odd man out:
What are the adverse effects of corrosion?
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give a reason why rust turns moist red litmus blue.
_______ is an alloy made from iron, carbon and chromium.
Stainless steel is an alloy of _______.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Match the columns.
| Group A | Group B |
| 1) Electroplating | a) Pressure cooker |
| 2) Anodising | b) Silver plated spoons |
| c) Coating of tin on copper | |
| d) Coating of Zinc on iron |
Write the name.
An alloy of copper and tin-
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Draw a neat labelled diagram.
Anodizing
Complete flow chart given below.
Give the equation for the formation of rust.
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
Which among the following alloys contain mercury as one of its constituents?
State whether the following statement is true or false:
Ships suffer a lot of damage though they are painted.
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
