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प्रश्न
In the extraction of aluminium: Write the function and formula of cryolite in the extraction of aluminium.
In the extraction of aluminium Write the function and chemical formula of cryolite
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उत्तर
Cryolite is added to the molten mixture of alumina to reduce the melting point. The formula of cryolite is Na3AlF6.
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संबंधित प्रश्न
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Name one ore of aluminium. Name the aluminium compound present in this ore and write its chemical formula.
The two metals which are extracted by means of electrolytic reduction of their molten salts are ______.
The metal which can be extracted simply by heating the cinnabar ore in air is ______.
A sulphide ore is converted into metal oxide by the process of ______.
When an object made of metal A is kept in air for a considerable time, it loses its shine and becomes almost black due to the formation of a layer of substance B. When an object made of another metal C is kept in damp air for a considerable time, it gets covered with a green layer of substance D. Metal A is the best conductor of electricity whereas metal C is the next best conductor of electricity.
- What is metal А?
- What is metal C?
- Name the substance B.
- Name the substance D.
- What type of chemical can be used to remove the green layer from metal C and clean it? Why?
Distinguish between ‘roasting’ and ‘calcination’. Which of these two is used for sulphide ores and why?
Define the following term.
Gangue
Name the ore of mercury. With the help of balanced chemical equations, explain the process of extraction of mercury from its ore.
Name the following:
Two metals which are found in the free or native state.
What is meant by refining of metals?
How are metals refined by the electrolytic methods?
Write equations for each of the above metal which reacts with water.
Write the name.
Strongly heating carbonate ores in insufficient air -
Read the following passage and answer the questions.
According to the reactivity series, zinc is more reactive than iron, iron is more reactive than silver. During study of this, a student dipped the iron nails in silver nitrate solution.
- What is reactivity series?
- What will happen when iron nails are dipped in silver nitrate solution?
- Which type of reaction happens when iron metal reacts with silver nitrate solution?
- What will happen if a zinc rod is used instead of iron nail?
Which of the following metals exist in their native state in nature?
(i) Cu
(ii) Au
(iii) Zn
(iv) Ag
2 mL each of concentrated HCl, HNO3 and a mixture of concentrated HCl and concentrated HNO3 in the ratio of 3 : 1 were taken in test tubes labelled as A, B and C. A small piece of metal was put in each test tube. No change occurred in test tubes A and B but the metal got dissolved in test tube C respectively. The metal could be
During extraction of metals, electolytic refining is used to obtain pure metals.
(a) Which material will be used as anode and cathode for refining of silver metal by this process?
(b) Suggest a suitable electrolyte also.
(c) In this electrolytic cell, where do we get pure silver after passing electric current?
Give the reaction involved during extraction of zinc from its ore by
- roasting of zinc ore
- calcination of zinc ore
Two ores A and B were taken. On heating ore A gives CO2 whereas, ore B gives SO2. What steps will you take to convert them into metals?
