Lakhmir Singh solutions for केमिस्ट्री [इंग्रजी] इयत्ता १० आईसीएसई chapter 7 - Metallurgy [Latest edition]

State whether the following statement is True or False.

Metals are found in the reduced form in the combined state.

State whether the following statement is True or False.

Bauxite is an ore of aluminium.

State whether the following statement is True or False.

The removal of unwanted impurities from the ore is called ore dressing.

State whether the following statement is True or False.

Hydrolytic method is used for the concentration of sulphides ores.

______ and ______ metals occur in a free state as well as in the combined state.

The minerals from which the metals can be conveniently and profitably extracted are called ______.

The ores of iron are ______ and ______.

The ______ method is based on the principle of differences in the densities of ore and gangue.

Which of the following is an ore of copper?

The method based on the preferential wetting of sulphides ores by oil and gangue by water is ______.

The method used for extracting precious metals is ______.

Name the important ores of zinc.

Write the name and formula of two ores of the following:

Iron

Define the term : Ore

What is the difference between a mineral and an ore?

Define the term slag with examples of acidic and basic fluxes.

Give the principles of the hydrolytic method.

Give the principles of electromagnetic separation.

Give the principles of the froth floatation process.

Explain the chemical method for the extraction of metal with examples.

State whether the following statement is True or False.

Roasting is the process of converting an ore into its oxide by heating strongly at a temperature below its melting point in excess of air.

State whether the following statement is True or False.

Aluminium metal is extracted by the electrolysis of its molten oxide.

State whether the following statement is True or False.

Liquation process is employed when the impurity is less fusible than metal itself.

______ process is commonly used for carbonate ores.

The arrangement of metals in decreasing order of their reactivity is called ______.

The ore of iron is reduced in blast furnace by using ______ and ______.

Lead is obtained by reduction of their oxides with:

Which of the following method is used to purify mercury, zinc and cadmium?

Which of the following is purified by electrorefining?

Define roasting.

Define calcination.

Write a note on the extraction of highly reactive metals.

Define the process of liquation with examples.

Give the basis for the purification of metal by distillation.

Give the basis for the purification of metal by oxidation.

Explain electrorefining with a labelled diagram.

State whether the following statement is True or False.

Magnetite is an ore of aluminium.

State whether the following statement is True or False.

Pure alumina is obtained from bauxite ore by Baeyer’s process.

State whether the following statement is True or False.

Aluminium is malleable but not ductile.

State whether the following statement is True or False.

Pure aluminium is corroded by pure water.

State whether the following statement is True or False.

A thermite is a mixture of 3 parts of ferric oxide and 1 part of aluminium powder.

Aluminium was discovered by ______.

______ contains 60% Al₂O₃ and rest being sand, ferric and titanium oxide.

The bottom layer of the electrolytic cell during refining of aluminium is formed by ______ aluminium.

Aluminium is a powerful ______ agent.

Aluminium is used in ______ as it is light strong and corrosion resistant.

Which of the following is an ore of aluminium?

Red mud consists of ferric oxide, sand which are removed by ______.

Which of the following alloys does not contain copper?

Brass is an alloy of ______.

Write the chemical formulae of the main ore of aluminium.

Write the chemical formulae of the main ore of iron.

Give the chemical names and formulae of the main ores of zinc.

Complete the following reaction:

\[\ce{Al2O3 + 2NaOH + 3H2O ->[473 - 923 K]}\]

Complete the following reaction:

______ \[\ce{->[Heat][1473 K] Al2O3 + 3H2O}\]

Complete the following reaction:

______ \[\ce{+ 2H2O -> NaOH + Al(OH)3 ↓}\]

Write the electrode reactions involved in Hall-Heroult’s process.

Write the action of air, water, acids, bases and non metals on aluminium.

State two important uses of following metals: 

Uses of iron   

Give the uses of zinc.

Define:

Alloy

State two important uses of the following metal. 

Uses of magnesium  

Write the uses of invar.

Write the uses of gun metal.

Manufacturing of a car requires special consideration of its overall weight. More weight of the car means more consumption of fuel during the driving. Hence, engineers are always in search of such an alloy that can be used to reduce the overall weight of a car without compromising on the strength of components and hence the safety of the passengers.

Considering the scenario discussed above, suggest which type of alloy might be suitable for the automobile industry? Also, do research, using the internet, to find out what kind of metals or alloys automobile companies are using currently to manufacture cars.

True or False.

Cinnabar is an ore of mercury.

True or False.

Hydrolytic method is also known as gravity separation.

True or False.

Leaching is based on the principle of preferential wetting of sulphide ores by oil and gangue by water.

True or False.

Carbon is placed just below zinc in the reactivity series.

True or False.

In electrorefining, impure metal is made the cathode.