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प्रश्न
Gold and silver are active metals.
पर्याय
Right
Wrong
उत्तर
Gold and silver are active metals- Wrong
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संबंधित प्रश्न
In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?
Fill in the following blank with suitable word:
The non-metal present in steel is ............
Name the chemical compound which is electrolysed in molten state to obtain aluminium metal. Which gas is evolved during this process?
Name the chemical compound which is electrolysed in molten state to obtain sodium metal. Which gas is produced in this process?
In an electrolytic tank, aluminium metal is being extracted by the electrolysis of molten aluminium oxide using carbon electrodes. It is observed that one of the carbon electrodes is gradually burnt away and has to be replaced.
(a) Which carbon electrode (cathode or anode) is burnt away?
(b) Why is this carbon electrode burnt away?
Compare the process of calcination and roasting.
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 ______.
Which one of the following is not true of metal :
Metals form non-polar covalent compounds
choose the most appropriate term to match the given description.
Heating of the ore in the absence of air to high temperature
Froth floatation process is generally used to concentrate ______ ores.
_______ is the least reactive metal.
Explain the following reaction with the balanced equation.
Zinc carbonate is heated strongly in limited supply of air
Explain concept with example/explain with the help of a balanced equation.
Roasting
Explain concept with example/explain with the help of a balanced equation.
Calcination
Explain in brief types of extraction of less reactive metals according to their reactivity.
The poorest conductor of heat among metals is ____________.
In thermite welding a mixture of ____________ is ignited with a burning magnesium ribbon which produces molten iron metal as a large amount of heat is evolved.
Which of the following metals exist in their native state in nature?
(i) Cu
(ii) Au
(iii) Zn
(iv) Ag
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Give the reason why the above reaction is known as a thermite reaction.
Assertion (A): The extraction of metals from their sulphide ores cannot take place without roasting the ore.
Reason (R): Roasting converts sulphide ores directly into metals.
