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प्रश्न
Find the odd one out and give its explanation.
विकल्प
Zinc coating
Tinning
Electroplating
Calcination
उत्तर
Calcination
Explanation-
Calcination is a process involved in extraction of carbonate ores while others are methods used for prevention of corrosion.
APPEARS IN
संबंधित प्रश्न
Give reasons.
Carbonate and sulphide ores are usually converted into oxides during the process of extraction.
Write the composition of the alloy called bronze.
Name one metal which is extracted by electrolytic reduction.
Which one of the methods given in column I is applied for the extraction of each of the metals given in column II:
| Column I | Column II |
| Electrolytic reduction | Aluminium |
| Reduction with Carbon | Zinc |
| Reduction with Aluminium | Sodium |
| Iron | |
| Manganese | |
| Tin |
Name two metals which occur in nature in free state as well as in combined state.
Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.
Describe with one example, how moderately reactive metals (which are in the middle of reactivity series) are extracted.
Which metal is extracted from cinnabar ore?
Name one ore of mercury. Which mercury compound is present in this ore? Write its chemical formula.
Give the chemical formula of :
Bauxite
Give the chemical formula of :
Cryolite
Explain the following:
Galvanization protects iron from rusting.
X is an element in the form of a powder. X burns in oxygen and the product is soluble in water. The solution is tested with litmus. Write down only the word which will correctly complete each of the following sentences:
(a) If X is a metal, then the litmus will turn ______.
(b) If X is a non-metal, then the litmus will turn ______.
(c) If X is a reactive metal, then ______ will be evolved, when X reacts with dilute sulphuric acid.
(d) If X is a non -metal, it will form _ oxide, which will form ______ solution with water.
(e) If X is a non -metal, it will not conduct electricity unless it is carbon in the form of ______.
State three objectives achieved during the roasting of ores.
Name the following :
The Process of heating an ore to a high temperature in the presence of air.
Explain the characteristics of ionic compounds.
Which of the statements about the reaction, \[\ce{ZnO + CO -> Zn + CO2}\] is correct?
Which of the following metals exist in their native state in nature?
(i) Cu
(ii) Au
(iii) Zn
(iv) Ag
Give the reaction involved during extraction of zinc from its ore by
- roasting of zinc ore
- calcination of zinc ore
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.
