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प्रश्न
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
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उत्तर
- The slow process of decay or distinction ions of a metal due to the effect of air, moisture, acids, alkalies, or other chemicals on it is called corrosion.
- Ordinarily, gold ornaments do not get corroded.
- Gold is one of the least reactive metals. It does not react with air, moisture, sweat, or ordinary pollutants in air or water. Hence, it does not get corroded.
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संबंधित प्रश्न
What is an alloy?
Tinning : Tin : : Galvanizing : _________
Why do we apply paint on iron articles?
Which metals do not corrode easily?
Explain why rusting of iron objects is faster in coastal areas than in deserts.
Explain why Iron sheets are coated with zinc during galvanization.
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
What is anodising? Give its applications.
The chemical reaction involved in the corrosion of iron metal is that of:
(a) oxidation as well as displacement
(b) reduction as well as combination
(c) oxidation as well as combination
(d) reduction as well as displacement
Fill in the following blanks with suitable words:
Tiffin boxes are electroplated with .............. but car bumpers are electroplated with ............... to protect them from rusting.
Name the metal which is a constituent of blood pigment?
Explain how the activity series accounts for each of the following:
tendency to corrosion
State under what conditions corrosion is faster ?
Corrosion can be an advantage in some case.Explain ?
Compare roasting and calcination.
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
Observe the following picture a write down the chemical reaction with the explanation.
What is done to prevent corrosion of metals?
Answer the following question.
List two properties of alloys.
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.
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?
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
Complete flow chart given below.
The process of coating the surface of the metal with a thin layer of zinc is called ______
What is rust?
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 ____________.
Copper objects lose their shine and form green coating of ____________.
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
Explain the chemical reactions in rusting of iron.
In ______ process a layer of molten tin is deposited on metals.
