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प्रश्न
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?
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उत्तर
- The minerals from which the metal can be separated economically are called ores.
- The extraction of metals from their ores by various methods of separation and further purification to obtain pure metals are involved in the branch of metallurgy.
The extraction of metals from their ores and then refining them for use is known as metallurgy. - Metals such as silver, gold and platinum are found in free state.
- Metals are found in combined states as their salts such as oxides, carbonates, sulphides, and nitrates.
- The unwanted impurities of soil, sand, rocky substances, etc., present in the ore are called gangue.
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संबंधित प्रश्न
A man went door to door posing as a goldsmith. He promised to bring back the glitter of old and dull gold ornaments. An unsuspecting lady gave a set of gold bangles to him which he dipped in a particular solution. The bangles sparkled like new but their weight was reduced drastically. The lady was upset, but after a futile argument, the man beat a hasty retreat. Can you play the detective to find out the nature of the solution he had used?
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Define the term gangue.
Name the electrode at which aluminium metal is produced.
The metal which is always present in an amalgam is ______.
The articles made of silver metal become dark on prolonged exposure to air. This is due to the formation of a layer of its ______.
An element A which is a part of common salt and kept under kerosene reacts with another element B of atomic number 17 to give a product C. When an aqueous solution of product C is electrolysed then a compound D is formed and two gases are liberated.
- What are A and B?
- Identify C and D.
- What will be the action of C on litmus solution? Why?
- State whether element B is a solid, liquid or gas at room temperature.
- Write formula of the compound formed when element B reacts with an element E having atomic number 5.
State why aluminium is extracted from its oxide by electrolysis while copper, lead, iron by reducing agents and mercury and silver by thermal decomposition.
Define the following term.
Gangue
Complete the incomplete statement with missing word:
Metals are malleable while non-metals are ______.
How many valence electrons are present in non- metals?
Name a non- metal that has a metallic luster and sublimes on heating.
Answer the following question :
What is the difference between calcination and roasting.
Name the following :
The Process of heating an ore to a high temperature in the presence of air.
Carbon cannot reduce the oxides of sodium, magnesium, and aluminum to their respective metals. Why? Where are these metals placed in the reactivity series? How are these metals obtained from their ores? Take an example to explain the process of extraction along with chemical equations.
Zinc sulphide : Roasting : : zinc carbonate : _______
Write the name.
Extraction of aluminium from alumina-
Explain the following reaction with the balanced equation.
Dry aluminium hydroxide is ignited at 1000 °C
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?
