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प्रश्न
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?
उत्तर
Metal P is Zn (zinc), Q is Sn (tin), R is Pb (lead) and S is Fe (iron).
We arrive to the following conclusion:
Metal P (zinc) is used to form a thin layer on metal S (iron). The process of thin coating of zinc layer on iron objects is called galvanisation. This thin coating of zinc layer on iron objects protects it from corrosion (zinc is a highly reactive metal. It does not rust even in moisture because it forms a thin coat of zinc oxide on reacting with air).
Metal Q (tin) is used for electroplating tiffin boxes made of metal S (iron). This tin coating prevents the corrosion of iron. However, tin coating provides only outside protection.
Metal R (lead) is used in making car batteries. Metal Q (tin) and metal R (lead) are combined together to form an alloy called solder.
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संबंधित प्रश्न
Give reasons:
Platinum, gold and silver are used to make jewellery.
Two methods by which rusting of iron can be prevented are ______ and ______.
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 blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
What is corrosion?
What is the corrosion of iron known as?
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
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?
Name the metal which is a constituent of blood pigment?
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 done to prevent corrosion of metals?
Write three methods of preventing rusting of iron.
What is "rusting"? Describe with a labelled diagram an activity to investigate the conditions under which iron rusts.
Explain the term – rusting and give a word equation for the formation of rust. If polished iron nails are kept in three separate test tubes, state the contents in each test tube required, to prove the conditions for rusting.
State whether the statement given below is true or false. If false write the correct statement.
Graphite is a lustrous non-metal which conducts electricity.
_______ is an alloy made from iron, carbon and chromium.
Draw a neat labelled diagram.
Anodizing
What is rust?
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.
