Advertisements
Advertisements
प्रश्न
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
उत्तर
Manganese is extracted from its oxide (Manganese dioxide or MnO2 ) by using aluminium as the reducing agent. Because aluminium is more reactive than manganese and is placed above it in the reactivity series, aluminium can easily displace manganese from its oxide to liberate the metal.
Manganese dioxide is heated with aluminium powder to produce manganese.
3MnO2(s) + 4Al(s) → 3Mn (l) + 2Al2O3(s) + Heat
The reaction is highly exothermic and huge amount of heat is liberated. Thus, manganese will be produced in molten (liquid) state.
APPEARS IN
संबंधित प्रश्न
Name a reducing agent that may be used to obtain manganese from manganese dioxide.
Name two metals which are highly resistant to corrosion.
Name the gas produced when calamine ore is calcined.
Which of the following metals can be obtained from haematite ore?
(a) copper
(b) sodium
(c) zinc
(d) iron
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.
(a) What is metal A?
(b) What is metal C?
(c) Name the substance B.
(d) Name the substance D.
An element has its electron configuration as 2,8,8,2. Now answer the following questions.
a) What is the atomic number of this element?
b) What is the group of this element?
c) To which period does this element belong?
How an ore is concentrated by froth floatation process?
Iron is _______.
Mercury, silver, gold are highly reactive metals.
Which of the statements about the reaction, \[\ce{ZnO + CO -> Zn + CO2}\] is correct?
