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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’.
संबंधित प्रश्न
What are alloys?
Explain why rusting of iron objects is faster in coastal areas than in deserts.
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 type of chemical reaction is involved in the corrosion of iron?
Explain why, iron sheets are coated with zinc.
In one method of rust prevention, the iron is not coated with anything. Which is this method?
The corrosion of iron is called ______.
Why is an iron grill painted frequently?
Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
Give the constituents of brass.
Name five methods of preventing rusting of iron.
In stainless steel alloy, iron metal is mixed with ______.
Explain how the activity series accounts for each of the following:
tendency to corrosion
Corrosion can be an advantage in some case.Explain ?
Compare roasting and calcination.
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 ..................................................................
What is ‘rusting’?
Give reason.
Copper and brass utensils should be tinned.
Stainless steel is an alloy of _______.
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the name.
An alloy of copper and tin-
Write scientific reason.
On exposure to air, silver articles turn blackish after some time.
Write scientific reason.
Coins are made from metals and alloys.
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.
Amalgam is an alloy of ____________.
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:
Galvanisation is a process used to prevent the rusting of which of the following?
Give an example of a chemical reaction for the following situation:
Sound is produced
In ______ process a layer of molten tin is deposited on metals.
