Advertisements
Advertisements
प्रश्न
In the electrolytic reduction of alumina, the lining of graphite acts as an anode.
विकल्प
Right
Wrong
Advertisements
उत्तर
In the electrolytic reduction of alumina, the lining of graphite acts as an anode- Wrong
APPEARS IN
संबंधित प्रश्न
Define the Ore.
Name two metals which are found in nature in the free state.
Name the gas in air which tarnishes silver articles slowly.
Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.
The metal which can be extracted from the bauxite ore is:
(a) Na
(b) Mn
(c) Al
(d) Hg
Which of the following pair of metals exists in their native state in nature?
(a) Ag and Hg
(b) Ag and Zn
(c) Au and Hg
(d) Au and Ag
State three objectives achieved during the roasting of ores.
Some metallic oxides can be reduced by hydrogen, carbon and carbon monoxide and some cannot. Explain.
Give reasons, why aluminum is used in:
In aluminiothermy
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 ______.
Define calcination.
Iron is _______.
Write the name.
The process of strong heating of carbonate ores in insufficient air–
Write the molecular formulae of the following compound.
Cryolite
Explain the following reaction with the balanced equation.
Ferric oxide is reacted with aluminium.
Explain concept with example/explain with the help of a balanced equation.
Ionic bond and ionic compounds
An alloy is
Why should the metal sulphides and carbonates be converted to metal oxides in the process of extraction of metal from them?
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.
A mineral from which the metal can be extracted economically and conveniently is known as ______.
