Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
Revision Question Bank
Metals and Non-Metals
1. Name a metal which is most malleable and ductile.
Sol.
Silver is the metal which is most malleable and ductile
2. A green layer is gradually formed on a copper plate left exposed to air for a week in a
bathroom. What could this green substance be?
Sol.
This green layer is basic copper carbonate CuCO3.
Cu(OH)2. This is due to the reaction of copper with moist air.
3. Select metalloids from the following elements.
(a) Bismuth
(b) Copper
(c) Zinc
(d) Arsenic
(e) Iron
Sol.
Arsenic is a metalloid while the remaining elements are metals.
4. Name any two non-metals which are used in industry. How is each one of them important
to us?
Sol.
Nitrogen and sulphur are non-metals and are widely used in industries. Nitrogen is used
in the manufacture of ammonia, nitric acid and fertilisers. Sulphur is used in the
manufacture of sulphuric acid, fungicide, gun powder and in vulcanisation of
rubber.
5. Give reasons for the following
(a) Metals are regarded as electropositive elements.
(b) When a piece of copper metal is added to a solution of zinc sulphate, no change takes
place but the blue colour of copper sulphate fades away when a piece of zinc is placed in
its solution.
(c) Articles made of aluminium do not corrode even though aluminium is an active metal.
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
7
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
Sol.
(a) Metals are elements having upto 3 electrons in their outermost shell. They react by
losing electrons and forming positive ions. Hence, they are regarded as electropositive
elements,
(b) Zinc is more reactive than copper. So, when a piece of copper metal is added to a
solution of zinc sulphate Cu is unable to displace Zn in ZnSO4 solution and hence no
reaction takes place. But when a piece of zinc is added to copper sulphate solution, Zn
easily displaces Cu from CuSO4 solution to form ZnSO4 and so the blue colour of CuSO4
solution fades away.
(c) Aluminium is an active metal, so it quickly begins to corrode, when it comes in contact
with moist air and forms aluminium oxide all over the Al metal. The thin aluminium oxide
layer formed on the surface of the aluminium objects protects the lower lying layers from
further corrosion as moist air is not able to pass through this aluminium oxide layer.
Corrosion of aluminium is thus useful.
6. What are strategic metals? Give one example also.
Sol.
Elements which are essential for a country's economy and its defence are called strategic
metals. e.g., titanium, chromium, zirconium and manganese.
7. Write chemical equations for reactions taking place when
(a) manganese dioxide is heated with aluminium powders.
(b) steam is passed over hot iron.
Sol.
When manganese dioxide is heated with aluminium powder, the following
reaction
takes place,
(a) 3MnO2  s  
Manganese
dioxide
4Al  s 
Aluminium powder


 3Mn  l 
Manganese metal
 2Al2O3  s 
Aluminium oxide
(b) When steam is passed over hot iron
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
8
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
3Fe 4H2O 
 Fe3O4  4H2
Iron
steam
Iron(II,III)
oxide
Hydrogen
8. What is corrosion of metals ? Name one metal which does not corrode and one which
corrodes on being kept in atmosphere.
Sol.
The reaction of metals at their surface with the surrounding atmosphere like air and
moisture is called corrosion. Gold (and platinum) does not corrode, whereas iron
corrodes easily.
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
9
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
Metals and Non-metals {Chapter Test}
M:M: 30
1.
M: Time: 40Mins.
Give the steps involved in the extraction of metals of low and medium reactivity from
their respective sulphide ores.
[4]
Sol:
For metals, low in reactivity like Hg (mercury), the following steps are involved in their
extraction
(i) Ore 
 Metal oxide (by heating in air roasting)
2ZnS  3O2 
 2ZnO
Mercury(II)
sulphate
Mercury(II)oxide
Oxygen
 2SO2
sulphate
dioxide
(ii) Metal oxide 
 Metal (heating)
2HgO
Mercury(II)oxide
Heat

 Reduction  2Hg  O2
Mercury
Oxygen
(iii) Refining of metal.
For metals, medium in reactivity like zinc (Zn), the following steps are involved in their
extraction
(i) Ore 
 metal oxide (roasting)
o
500 C
2ZnS  3O2 
 2ZnO  2SO2
Zinc
sulphate
Zinc
oxide
Oxygen
sulphate
dioxide
 metal (using reducing agent)
(ii) Metal oxide 
ZnO 
Zinc
oxide
o
400 C

 Zn  CO
C
Carbon
Reducing
agent


Zinc
carbon
monoxide
(iii) Refining of metal.
2.
What are alloys? How are they made? Name the constituents and uses of brass, bronze
and solder.
[4]
Sol:
Alloys are the homogeneous mixture of two or more metals/metals with a non-metal.
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
10
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
They are made by mixing the metals in the molten state and then cooling the mixture.
Constituents and Uses of Alloys
3.
Alloy
Constituents
Brass
copper and zinc
Bronze
copper and tin
Solder
lead and tin
Uses
In making utensils and
taps
In making medals and
statues.
In welding of electrical
wires.
Give reasons for the following
[5]
(a) Aluminium oxide is amphoteric oxide.
(b) Metals displace hydrogen gas from acids.
(c) Iron articles are frequently painted.
(d) Iron sheets are coated with zinc layer.
Sol:
(a) Aluminium oxide is amphoteric oxide because it shows the properties of both acidic
and basic oxides. It reacts with both acids and bases to form salt and water.
(b) Metals when react with acids, donate electrons to hydrogen ions present in acid to
form hydrogen atoms which combines further to form hydrogen gas.
(c) Iron articles when come in contact with oxygen and water, form rust (a flaky
substance) on its surface and slowly loses their strength. To avoid this, iron articles are
painted frequently.
(d) Iron sheets are coated with zinc (galvanisation) so as to prevent iron from
rusting.
4.
Explain the following
[5]
(a) Reactivity of Al decreases if it is dipped in
(b) Carbon cannot reduce the oxides of Na or Mg.
(c) NaCl is not a conductor of electricity in solid state whereas it does conduct
electricity in aqueous solution as well as in molten state.
(d) Iron articles are galvanised.
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
11
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
(e) Metals like Na, K, Ca and Mg are never found in their free state in nature.
Sol:
(a) HNO3 is an oxidising agent. When aluminium is dipped in HNO3, an oxide
layer of aluminium is formed on the surface of it. Which prevents it from further reaction.
(b) Na or Mg have great affinity towards oxygen so cannot be reduced by carbon.
(c) NaCl furnishes free ions in both molten as well as in aqueous solution hence becomes
conducting. In solid state, free ions are not present, so it is a non-conductor
of
electricity.
(d) To prevent the iron articles from corrosion (rusting), they are galvanised.
(e) It is because they are highly reactive in nature. They are found in the form of their
compounds.
5.
Discuss reactivity of different metals in reactivity series with water.
[3]
Sol:
(i) Reactive metals react with cold water and reaction results in fire.
2Na (s) + 2H2O 
 2NaOH + H2 + Energy
(ii) Less reactive metals also release hydrogen, but no fire occurs.
 Ca(OH)2(aq)+ H2(g)
Ca(s)+ 2H2O(l) 
(iii) Metals such as magnesium react with hot water.
 Mg (OH)2 + H2
Mg + 2H2O 
(iv) Less reactive metals like Al, Zn, etc react with steam.
2Al(s) + 3H2O(s) 
 Al2O3(s)+3H2(g)
(v) Least reactive metals like Cu, Pt, etc do not react even with steam.
6.
What is meant by refining of metals? Describe the electrolytic refining of copper with a
neat labelled diagram.
[4]
Sol:
The process of purifying impure metals (obtained from reduction processes) is called
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
12
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
refining of metals.
Electrolytic Refining of Metal (Refining through electrolysis).
Process During this process, a thick strip of impure Cu metal is used as anode and a thin
strip of pure metal is used as cathode. A solution of salt of the metal CuSO4 is used as
electrolyte. When electric current is passed through the acidified
electrolyte solution, copper dissolves from the anode terminal and releases Cu2+ ions in
the electrolyte.
These ions deposit on cathode as pure metal. Impurities such as gold, Ft, etc fall down as
anode mud.
7.
What is rusting? Describe an activity to find out conditions under which iron rusts.
[4]
Sol:
Rusting is defined as the process in which iron surface corrodes due to deposition of
oxides of iron on its surface on reacting with air and moisture.
Activity
(i) Take three test-tubes and place two or three iron nails in each of them.
(ii) Pour some water in .A and cork the test tube.
(iii) Pour boiled water and vegetable oil in B and cork the test tube.
(iv) Put anhydrous CaCl2 in C and cork it.
(v) Wait for two to three days.
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
13
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
Observations in test tube,
A - Nails get rusted as exposed to air and water.
B - No rust as air supply is cut by oil.
C - No rust as CaCl2 absorbs moisture from the air.
Conclusion Both air and water cause rusting.
8.
(a) In what forms are metals found in nature?
[2]
(b) How do metals react with oxygen and water? Give examples to explain.
Sol:
(a) Metals are found in nature as oxides, sulphides and carbonates.
(b) (i) Reaction of metals with oxygen Metals react with oxygen to give oxides.
For example,
2Mg
Magnessium

 O2 
 2MgO
Oxygen
Magnessium
oxide
(ii) Reaction of metals with water Metals react with water to give hydroxides. Generally
H2 is evolved during this process.
For example,
Mg
Magnessium
s

 2H2O  l  

water
Mg OH 2 
Magnessium
hydroxide
9.
H
2
Hydrogen
Compare metals and non-metals on the basis of their
(a) physical state
(b) luster
(c) ductility
(d) melting and boiling points
[5]
(e) density
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
14
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
Sol:
(a) Physical state Metals exist in solid state (except mercury) while non-metals are
either solids or gases at room temperature (except bromine which is liquid).
(b) Lustre Metals have a lustrous appearance and can be polished. Non-metals have a
dull appearance.
(c) Ductility Metals are highly ductile, while non-metals are not.
(d) Melting and boiling points Metals have high melting and boiling point, while
non-metals have low melting and boiling point.
(e) Density Metals have high density, while non-metals have low density.
10. (a) Given below are the steps for extraction of copper from its ore. Write the reactions
involved.
[5]
(i) Roasting of copper (I) sulphide,
(ii) Reduction of copper (I) oxide with copper (I) sulphide.
(iii) Electrolytic refining
(b) Draw a neat and well labelled diagram for electrolytic refining of copper.
Sol:
Heat
(a) (i)2Cu2S+3O2 
2Cu2O+2SO2
Heat
(ii) 2Cu2O+Cu2S 
6Cu + SO2
(iii) Electrolytic refining
 Cu2+ +2e–
At anode Cu 
At cathode Cu2+ +2e– 
 Cu
(b) (i) A thick block of the impure metal is made anode (+ve).
(ii) A thin strip of pure metal is made cathode (–ve).
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
15
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
11. A metal M does not liberate hydrogen from acids but reacts with oxygen to give a black
coloured product. Identify M and black coloured product and also explain the reaction.
[2]
Sol:
M is copper.
Copper does not react with acids but reacts with oxygen to form copper oxide.
2Cu
Copper
 M

O2 
 2CuO
Oxygen
Copper(II)oxide
 Black 
12. On reaction of Zn with NaOH, which gas is released?
[1]
Sol:
Hydrogen gas
13. What are ionic compounds? What are their important properties? Give one example of
ionic compound and give its electron dot diagram.
[3]
Sol:
The compounds which are formed by transfer of one or more electrons from the
outermost shell of an atom to another atom are called ionic compounds. In other words,
we can say that the compounds which are made up of ions are known as ionic compounds.
Their important properties are as follows
(i) They are in solid state and molecules are held together by strong forces (electrovalent
www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
16
Pioneer Education {The Best Way To Success}
IIT – JEE /AIPMT/NTSE/Olympiads Classes
bonds) so that they do not easily vaporise.
(ii) They have high melting and boiling points.
(iii) They do not conduct electricity in solid state but are good conductors in molten state
or when dissolved in water.
(iv) They are soluble in water but insoluble in organic solvents.
Example


NaCl  Na++Cl 
 N+ aCl–


Na  Cl : 
 Na Cl : 


www.pioneermathematics.com S.C.O. - 326, Sector 40–D, CHD. Phone: 9815527721, 4617721
17