Advertisements
Advertisements
प्रश्न
Write the name.
The process of extraction of aluminium from alumina-
Advertisements
उत्तर
The process of extraction of aluminium from alumina- Electrolytic reduction
APPEARS IN
संबंधित प्रश्न
Name the following:
The property possessed by metals by which they can be beaten into sheets.
Name a reducing agent that may be used to obtain manganese from manganese dioxide.
Write the composition of the alloy called bronze.
Fill in the following blank with suitable word:
The rocky material found with ores is called.............
Name one ore of sodium. Name the sodium compound present in this ore and write its chemical formula.
Name one ore of mercury. Which mercury compound is present in this ore? Write its chemical formula.
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.
Give the principles of electromagnetic separation.
Compare the process of calcination and roasting.
How are metals refined by the electrolytic methods?
Explain the following:
Galvanization protects iron from rusting.
Calcium, copper, lead, aluminium, zinc, chromium, magnesium, iron.
Choose the major metals from the list given above to make the following alloys:
(a) Stainless steel
(b) brass
Zinc blende is converted to oxide by ______ process.
Name the process used for the enrichment of sulphide ore.
Write the name.
The molecular formula of main ore of aluminium –
Explain the following reaction with the balanced equation.
Zinc sulphide is heated strongly in excess of air
Explain concept with example/explain with the help of a balanced equation.
Ionic bond and ionic compounds
Oxides of moderately reactive metals like Zinc, Iron, Nickel, Tin, Copper, etc. are reduced by using:
Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation of bubbles in reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions.
