Advertisements
Advertisements
प्रश्न
Find the odd one out and give its explanation.
पर्याय
Zinc coating
Tinning
Electroplating
Calcination
Advertisements
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
In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?
In the extraction of aluminium: Draw the diagram for the extraction of aluminium.
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.
What iron compound is present in haematite ore? Also write its chemical formula.
Name one ore of sodium. Name the sodium compound present in this ore and write its chemical formula.
Which gas is produced during the extraction of aluminium? At which electrode is this gas produced?
Manganese metal is extracted from manganese dioxide by a reduction process by making use of:
(a) carbon
(b) hydrogen
(c) electrolysis
(d) aluminium
The articles made of silver metal become dark on prolonged exposure to air. This is due to the formation of a layer of its:
(a) oxide
(b) hydride
(c) sulphide
(d) carbonate
Name : The metal which is liquid at room temperature.
To protect iron from rusting, it is coated with a thin layer of zinc. Name the process.
Name the following:
The process of heating an ore to a high temperature in the presence of air.
Name the methods by which concentrated ore is converted to metallic oxide.
State three objectives achieved during the roasting of ores.
Write the name.
The process of strong heating of carbonate ores in insufficient air–
Write the name.
The process of extraction of aluminium from alumina-
Write the molecular formulae of the following compound.
Sodium aluminate
Answer the questions on the following passage.
The minerals from which the metal can be separated economically are called ores. Ores contain many types of impurities such as soil, sand and rocky substances along with metal compounds. These impurities are called gangue.
Metals can be extracted from their ores by means of various methods of separation. The process of extraction of metal in a pure state from the ores is also a part of metallurgy.
Ores are taken out from the mines and the gangue is usually separated from the ore at the site itself by various methods. Then the ores are carried out to the place where metals are produced. Here metals are extracted in pure form. Then metals are further purified by different methods of purification. This entire process is called metallurgy. Most metals being reactive do not occur in nature in the free state but are found in combined state as their salts such as oxides, carbonates, sulphides, and nitrates. however, the most unreactive metals that are not affected by air, water and other natural factors like silver, gold, platinum, generally occur in a free state. The compounds of metals that occur in nature along with the impurities are called minerals.
- What are ores?
- Which processes are involved in the branch of metallurgy? What is metallurgy?
- Which metals are found in a free state?
- In what forms are metals found in combined state?
- What is gangue?
Explain the difference between Bayer’s process and Hall’s process by explaining the Bayer’s process.
Care must be taken while diluting concentrated nitric acid with water. Why?
