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प्रश्न
Complete flow chart given below.
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उत्तर
संबंधित प्रश्न
Define the Ore.
In the extraction of aluminium: Why is it necessary to replace anodes time to time?
A zinc ore on heating in air forms sulphur dioxide. Describe briefly any two stages involved in the conversion of this concentrated ore into zinc metal.
Name the electrode at which aluminium metal is produced.
Manganese metal is extracted from manganese dioxide by a reduction process by making use of ______.
During galvanisation, iron metal is given a thin coating of one of the following metals. This metal is:
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?
Name the following:
Two metals which are found in the free or native state.
What is passive iron?
The following questions relate to the extraction of aluminium by electrolysis.
Explain why it is necessary to renew the anode periodically.
Complete the incomplete statement with missing word:
Metals form positive ions while non- metals ______.
State three objectives achieved during the roasting of ores.
Observe the given figure of reactivity series of metals and answer the following questions:
Reactivity series of metals
- Name two metals which react with water.
- Name two moderately reactive metals.
- Name the most highly reactive metal and the most less reactive metal.
Extraction of moderately reactive elements is done by _______ and _______ method.
_______ is the least reactive metal.
Write the name.
The molecular formula of main ore of aluminium –
Explain the concept of Roasting.
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?
Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation of bubbles in reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions.
Care must be taken while diluting concentrated nitric acid with water. Why?
