Advertisements
Advertisements
प्रश्न
In the electrolytic reduction of alumina, the lining of graphite acts as an anode.
विकल्प
Right
Wrong
उत्तर
In the electrolytic reduction of alumina, the lining of graphite acts as an anode- Wrong
APPEARS IN
संबंधित प्रश्न
In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?
M is a metal above hydrogen in the activity series and its oxide has the formula M2O. This oxide when dissolved in water forms the corresponding hydroxide which is a good conductor of electricity. In the above context, answer the following:
1) What kind of combination exists between M and O?
2)How many electrons are there in the outermost shell of M?
3) Name the group to which M belongs.
4) State the reaction taking place at the cathode.
5) Name the product at the anode.
Write the composition of the alloy called bronze.
Name two metals which are highly resistant to corrosion.
Why are the metals like Na, K, Ca and Mg never found in their free state in nature?
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.
Which gas is produced during the extraction of aluminium? At which electrode is this gas produced?
Calamine ore can be used to extract one of the following metals. This metal is:
(a) copper
(b) mercury
(c) aluminium
(d) zinc
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?
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.
Aluminum is used in thermite welding:
what is thermit?
Explain the following:
Galvanization protects iron from rusting.
Complete the incomplete statement with missing word:
Metals are malleable while non-metals are ______.
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 ______.
Extraction of moderately reactive elements is done by _______ and _______ method.
Write the molecular formulae of the following compound.
Fluorspar
Explain the following reaction with the balanced equation.
Zinc oxide is treated with carbon
Explain the difference between Bayer’s process and Hall’s process by explaining the Bayer’s process.
The poorest conductor of heat among metals is ____________.
Which of the following metals exist in their native state in nature?
(i) Cu
(ii) Au
(iii) Zn
(iv) Ag
