Advertisements
Advertisements
प्रश्न
In the extraction of aluminium: Name the process of concentration of bauxite.
उत्तर
The process of concentration of bauxite is known as Bayer’s process.
APPEARS IN
संबंधित प्रश्न
Metallic oxides of zinc, magnesium and copper were heated with the following metals.
| Metal | Zinc | Magnesium | Copper |
| Zinc oxide | – | – | – |
| Magnesium oxide | – | – | – |
| Copper oxide | – | – | – |
In which cases will you find displacement reactions taking place?
Name one metal which is extracted by electrolytic reduction.
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.
Define the term ore.
Name the gas produced when calamine ore is calcined.
Which of the following is an iron ore?
(a) cinnabar
(b) calamine
(c) haematite
(d) rock salt
Which of the following metals are extracted by the electrolysis of their molten chlorides?
(a) Na and Hg
(b) Hg and Mg
(c) Na and Mg
(d) Cu and Fe
Zinc blende ore can be converted into zinc oxide by the process of:
(a) roasting
(b) hydrogenation
(c) chlorination
(d) calcination
A metal which exists as a liquid at room temperature is obtained by heating its sulphide ore in the presence of air.
(a) Name the metal and write its chemical symbol.
(b) Write the name and formula of the sulphide ore.
(c) Give the equations of chemical reactions involved in the production of metal from its sulphide ore.
(d) Name a common device in which this metal is used.
(e) Can this metal displace copper from copper sulphate solution? Why?
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?
Distinguish between ‘roasting’ and ‘calcination’. Which of these two is used for sulphide ores and why?
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?
Identify the process given in following passage and draw neat labelled diagram showing the process.
Electrolysis of molten mixture of alumina (melting point > 20000C) is done in a steel tank. The tank has a graphite lining on the inner side. This lining does the work of a cathode. A set of graphite rods dipped in the molten electrolyte works as anode. Cryolite (Na3AlF6) and fluorspar (CaF2) are added in the mixture to lower its melting point upto 10000C.
Correct the following statement :
Copper reacts with nitric acid to produce nitrogen dioxide.
Name the following:
A steel grey coloured solid non-metal.
Atomic number of aluminium is _______ and its electronic configuration is _______.
Find the odd one out and give its explanation.
Explain the following reaction with the balanced equation.
Chlorine dissolved in water
Explain the following reaction with the balanced equation.
Dry aluminium hydroxide is ignited at 1000 °C
Observe the following diagram and write answers.
- Name the method.
- Write anode reaction and cathode reaction.
- Why fluorspar and cryolite are added in the mixture?
