O LEVEL PAST PAER
QUESTIONS.______________________________________________________________________________________TOPIC
3: Atomic Structure / Chemical Bonding.
PAPER -1 MCQz1- Which statement is true about an atom?A- All the
elements have only one nucleon (mass) number.B- The nucleon (mass)
number can be less than the proton (atomic) number.C- The nucleon
(mass) number can equal to the proton (atomic) number.D- The number
of neutrons never equal the numbers of electrons. [J00/Q6]2-
Elements X and Y react to form an ionic compound of formula XY.
What could be the proton (atomic) numbers of X and Y?
[J00/Q8]XY
ABCD36812881616
3-Which ion has the most shells that contain electrons?A Al3+B
Be2+C N3D S2 [D02/Q5]4- The table gives data about four
substances.Which substance could be an ionic compound? D
Which substance contains covalent bonds, but also conducts
electricity?A brassB graphiteC iodineD steel [D02/Q9]5-A
[D02/Q14]6- For which of the following can graphite be used?A as
an abrasive onlyB as an abrasive and as an electrodeC as an
electrode and as a lubricantD as a lubricant only [J03/Q6]7- The
letters X, Y and Z represent different atoms. What can be deduced
from the proton numbers and nucleon numbers of X, Y and Z?A X and Y
are the same element.B X and Z are the same element.C X has more
protons than Y.D Z has more neutrons than Y. [J03/Q7]8- How does a
magnesium atom form a bond with an oxygen atom?A by giving one pair
of electrons to the oxygen atomB by sharing one pair of electrons,
both electrons provided by the magnesium atomC by sharing two pairs
of electrons, both pairs provided by the oxygen atomD by sharing
two pairs of electrons, each atom donating one pair of electrons.
[J03/Q8] 9- Which diagram represents the structure of the metal
sodium? C [J03/Q9]
10- Elements X and Y combine to form the gas XY2.What are X and
Y? C [J03/Q10] 11- Which of the following contains the same number
of electrons as an atom of neon?A C lB LiC Li+D O2 [J03/Q11] 12- A
researcher notices that atoms of an element X are releasing
energy.Why does this happen?A The atoms are affected by light.B The
atoms are radioactive.C The atoms react with argon in the air.D The
atoms are evaporating. [D03]13- An atom of element X is represented
by 73X.Which statement about an atom of X is correct?A It is in
Group III of the Periodic Table.B It is in Group VII of the
Periodic Table.C The total number of protons and electrons is 6.D
The total number of protons and neutrons is 10. . [D03]14- In which
pair of substances, does each have a giant molecular structure?A
diamond, iodineB diamond, silica (sand)C iodine, methaneD methane,
silica (sand) . [D03]15- In which substance is each carbon atom
covalently bonded to only three other atoms?A carbon dioxideB
diamondC graphiteD methane . [D03]16- How many electrons are shared
in the covalent bonding of a methane molecule?A 2B 4C 6D 8 .
[D03]17- The table gives information about the ability of four
substances to conduct electricity. C
. [D03]18- Two particles X and Y have the composition shown in
the table.
The particles X and Y areA metal atoms.B non-metal atoms.C
negative ions.D positive ions. . [D04]19-C [D04]20- Which compound
has both ionic and covalent bonds?A ammonium chlorideB carbon
dioxideC ethyl ethanoateD sodium chloride [D04]21- The experiment
shown is used to test potassium bromide crystals. The lamp does not
light. Distilled water is then added to the beaker and the lamp
lights. Which statement explains these results? A Electrons are
free to move in the solution when potassium bromide dissolves. B
Metal ions are free to move when potassium bromide melts. C Metal
ions are free to move when potassium reacts with water. D
Oppositely charged ions are free to move in the solution when
potassium bromide dissolves.[D04]22- A nucleon number.B number of
electrons.C number of neutrons.D number of protons. [Nov-2005]23-
The diagram shows the arrangement of electrons in a molecule of
compound YZ2. C [Nov-2005]24- Which two statements about a covalent
bond are correct?1 It can be formed between two metal atoms.2 It
can be formed between two non-metal atoms.3 It is formed by the
transfer of electrons between atoms.4 It is formed by sharing
electrons between atoms.A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4
[Nov-2005]25- Which statement explains why sodium chloride, NaCl,
has a lower melting point than magnesiumoxide, MgO?A Sodium
chloride is covalent but magnesium oxide is ionic.B Sodium is more
reactive than magnesium.C The attraction between Na+ and Cl is
weaker than that between Mg2+ and O2.D The melting point of sodium
is lower than that of magnesium. [Nov-2005]26- Four substances have
the following electrical properties.
What are these four substances? C [Nov-2005]/[June 2012]27- What
is the ratio of the volume of 2 g of hydrogen to the volume of 16 g
of methane, both volumesat r.t.p.?A 1 to 1 B 1 to 2 C 1 to 8 D 2 to
1 [Nov-2005]28- Hydrogen can form both H+ ions and H ions.Which
statement about these two ions is correct?A An H+ ion has no
electrons in its first shell.B An H+ ion has more protons than an H
ion.C An H ion has one more electron than an H+ ion.D An H ion is
formed when a hydrogen atom loses an electron. [June -2006]29-
Which graph shows the number of electrons in the outer shell of an
atom, plotted against theproton (atomic) number for the first ten
elements in the Periodic Table? [June -2006]/[June -2010] C
30- The symbols and electronic structures for some elements are
shown below.silicon, Si (2,8,4) oxygen, O (2,6) hydrogen, H
(1)fluorine, F (2,7) nitrogen, N (2,5)Which formula is correct for
a compound containing silicon? B [June -2006]31- Rubidium is in
Group I and bromine is in Group VII of the Periodic Table.How is a
compound formed between rubidium and bromine?A Each atom of bromine
shares an electron with an atom of rubidium.B Each atom of bromine
shares a pair of electrons with an atom of rubidium.C Each atom of
bromine gives an electron to an atom of rubidium.D Each atom of
bromine receives an electron from an atom of rubidium. [June
-2006]32- Which atom has the same electronic configuration as the
strontium ion?A calciumB kryptonC rubidiumD selenium [June
-2006]33- C [NOV -2006]34- A beam of particles contains neutrons,
n, protons, p, and electrons, e.The beam is passed between charged
plates.Which diagram shows how the particles are affected by the
plates? A
[NOV -2006]35- The table shows the properties of some
substances.Which substance is a covalent compound? B [NOV -2006]36-
The diagram shows the electrolysis of aqueous sodium chloride and
of molten sodium chloride.
Which substance has both positive ions and mobile electrons?A
aqueous sodium chlorideB copper wireC graphite electrodesD molten
sodium chloride [NOV -2006]37- Hydrogen can form both ionic and
covalent compounds.With which element will hydrogen form an ionic
compound?A carbonB chlorineC nitrogenD sodium [NOV -2006]38- A
[JUNE -2007]39- In which substance is each carbon atom
covalently bonded to only three other atoms?A carbon dioxideB
diamondC graphiteD methane [JUNE -2007]40- In which pair of
substances does each have a giant molecular structure?A diamond,
iodineB diamond, silica (sand)C iodine, methaneD methane, silica
(sand) [JUNE -2007]41- How does a magnesium atom form a bond with
an oxygen atom?A by giving one pair of electrons to the oxygen
atomB by sharing one pair of electrons, both electrons provided by
the magnesium atomC by sharing two pairs of electrons, both pairs
provided by the oxygen atomD by sharing two pairs of electrons,
each atom donating one pair of electrons [JUNE -2007]42- Which
material has the highest melting point?A ammoniaB methaneC sodium
chlorideD water [NOV -2007]43-A molecule of arsenic bromide, AsBr3,
has the structure shown. A
[NOV -2007]44- Which substance has a giant molecular structure
at room temperature?A methaneB sandC sodium chlorideD water [JUNE
-2008]45- When a covalent liquid boils its molecules become more
widely spaced.Which property of the molecules has the most
influence on the energy required to boil a covalentliquid?A the
forces of attraction between the moleculesB the reactivity of the
moleculesC the shape of the moleculesD the strength of the covalent
bonds in the molecules [JUNE -2008]46-A nucleon number.B number of
electrons.C number of neutrons.D proton number. [JUNE -2008]47-
Naturally occurring bromine has a relative atomic mass of 80 and
consists entirely of two isotopesof relative isotopic masses 79 and
81.What can be deduced about naturally-occurring bromine from this
information only?A Bromine isotopes have different numbers of
protons.B Bromine contains the two isotopes in equal proportions.C
Bromine has different oxidation states.D Bromine is radioactive.
[NOV -2008]/[June-2013]48- Which statement describes the conversion
of magnesium atoms to magnesium ions?A The change is reduction,
because there has been a gain of electrons.B The change is
oxidation, because there has been a loss of electrons.C The change
is reduction, because there has been a loss of electrons.D The
change is oxidation, because there has been a gain of electrons.
[NOV -2008]
49- In one molecule of carbon dioxide, CO2, what is the total
number of electrons present and howmany are involved in bonding
between the carbon and oxygen atoms? D [NOV -2008]50- Which
statement explains why magnesium oxide has a very high melting
point?A Magnesium atoms and oxygen atoms are joined by strong
covalent bonds.B The crystal lattice of magnesium oxide resembles
that of diamond.C The magnesium ions are strongly attracted to the
oxide ions.D The reaction between magnesium and oxygen is strongly
exothermic. [NOV -2008]51- When the experiment shown is set up, the
bulb lights, but there are no decomposition products atthe
electrodes. What is X? A aqueous sodium chloride B bromine C molten
sodium chloride D mercury [NOV -2008]
52- What are the products formed at the electrodes during the
electrolysis of molten magnesiumchloride between carbon electrodes?
C
[NOV -2008]53- An element X forms a positive ion with the
electronic structure 2,8,8.What is the proton (atomic) number of
X?A 16 B 17 C 18 D 19 [JUNE -2009]54- Which two substances are
elements with a giant molecular structure?A diamond and graphite C
methane and iodineB diamond and sand D methane and sand [JUNE
-2009]55- Which compound has both ionic and covalent bonds?A
ammonium chlorideB carbon dioxideC ethyl ethanoateD sodium chloride
[JUNE -2009]56- Which statement about the numbers of particles in
atoms is correct?Apart from hydrogen, most atoms containA more
neutrons than protons.B more protons than neutrons.C more electrons
than protons.D more protons than electrons. [JUNE -2009]57- B
[NOV -2009]58- Which statement is always true when two atoms
join together by a covalent bond?A One atom is a metal, the other
atom is a non-metal.B One atom loses one electron, the other atom
gains one electron.C The two atoms share one electron.D The two
atoms share two electrons. [NOV -2009]59- The diagram shows the
structures of diamond and graphite.
Which property do these substances have in common?A They are
giant structures.B They can act as lubricants.C They can conduct
electricity.D They contain only covalent bonds. [NOV -2009]60-
Calcium reacts with phosphorus to form the ionic compound calcium
phosphide.Which ions will this compound contain? A [NOV -2009]
62- Which pair of elements, when combined together, do not form
a covalent compound?A caesium and fluorineB nitrogen and chlorineC
phosphorus and fluorineD sulfur and chlorine [June 2010]63-
Hydrogen can form both H+ ions and H ions.Which one of the
statements below is correct?A An H+ ion has more protons than an H
ion.B An H+ ion has no electrons.C An H ion has one more electron
than an H+ ion.D An H ion is formed when a hydrogen atom loses an
electron. [Nov 2010]64- The diagram shows the molecule ethyl
propanoate.
How many bonding pairs of electrons are there in the molecule?A
13 B 16 C 17 D 20 [Nov 2010]65- Element X has the electronic
structure 2,8,5. Element Y has the electronic structure 2,8,7.What
is the likely formula of a compound containing only X and Y? [June
2011]A XY3 B X2Y3 C X3Y D X3Y266- Radium (Ra) is in the same group
of the Periodic Table as magnesium.What is the charge on a radium
ion?A 2 B 1 C 1+ D 2+ [Nov2011]67- Which statement about both
chlorine atoms and chloride ions is correct?A They are chemically
identical.B They are isotopes of chlorine.C They have the same
number of protons.D They have the same physical properties. [June
2011]68- How many of the molecules shown contain only one covalent
bond? Cl 2 H2 HCl N2 O2A 2 B 3 C 4 D 5 [Nov2011]69- Which compound
contains three elements?A aluminium chlorideB iron(III) oxideC
potassium oxideD sodium carbonate [Nov2011]70- What happens when
sodium chloride melts?A Covalent bonds in a giant lattice are
broken.B Electrons are released from atoms.C Electrostatic forces
of attraction between ions are overcome.D Molecules are separated
into ions. [Nov2011]71- Pentane, C5H12, has a higher boiling point
than propane, C3H8. Which statement explains thedifference in
boiling point?A Carbon-carbon single bonds are stronger than
carbon-hydrogen bonds.B Pentane has more covalent bonds to break.C
Pentane does not burn as easily as propane.D The forces of
attraction between pentane molecules are stronger than those
betweenpropane molecules [June 2012]72- Which substance will
conduct electricity without being chemically changed?A sodium
chloride solutionB solid ironC solid sodium chlorideD solid sulfur
[June 2012]73- Two particles have the compositions shown.
Which statement about X and Y is correct?A They are both
positively charged.B They are particles of the same element.C They
have the same mass number.D They have the same number of nucleons.
[Nov-2012]74- Which of the following is not a mixture?A ethanolB
petrolC steelD tap water [Nov-2012]75- Carbon and silicon are both
in Group IV of the Periodic Table, but at room temperature CO2 is
agas whereas SiO2 is a solid.Which statement explains this?A
Covalent bonding is weaker in CO2.B Covalent bonds in CO2 are
double bonds and in SiO2 the covalent bonds are single bonds.C CO2
is a covalent compound and SiO2 is ionic.D CO2 is a simple covalent
molecule and SiO2 is a macromolecule. [Nov-2012]76- Which substance
has metallic bonding? A
[Nov-2012]
77-Naturally-occurring bromine has a relative atomic mass of 80
and consists entirely of twoisotopes of relative atomic masses 79
and 81.What can be deduced about naturally-occurring bromine from
this information only?A Bromine contains the two isotopes in equal
proportions.B Bromine has different oxidation states.C Bromine
isotopes have different numbers of protons.D Bromine is
radioactive. [June 2013]78- Silicon carbide, SiC, has a structure
similar to diamond. Boron nitride, BN, has a structure similarto
graphite. Bronze is an alloy of copper and tin.Which statements
about SiC, BN and bronze are correct?1 All are bonded covalently.2
All except silicon carbide conduct electricity when solid.3 All
have high melting points.A 1 and 2 onlyB 1 and 3 onlyC 2 and 3
onlyD 1, 2 and 3 [June 2013]79- Sodium is in Group I of the
Periodic Table.When sodium combines with chlorine, what happens to
each sodium atom?A It gains one electron from one chlorine atom.B
It shares one electron with one chlorine atom.C It transfers one
electron to one chlorine atom.D It transfers two electrons to one
chlorine atom. [June 2013]80- Hydrogen and sulfur react to form the
compound hydrogen sulfide.Which row shows the type of bonding
between hydrogen and sulfur and the electrical conductivityof
liquid hydrogen sulfide? [June 2013]
81- Which elements exist as diatomic molecules at room
temperature?A hydrogen, oxygen, heliumB nitrogen, chlorine, neonC
nitrogen, oxygen, fluorineD oxygen, chlorine, helium [Nov-2013]82-
The diagram shows the electrolysis of aqueous sodium chloride and
of molten sodium chloride.
Which substance in the diagram has both positive ions and mobile
electrons?A aqueous sodium chlorideB copper wireC graphite
electrodesD molten sodium chloride [Nov-2013]83- Substance X has a
simple molecular structure and substance Y has a giant molecular
structure.Which row is correct? [Nov-2013] D
84- The diagram shows the structure of an ionic compound
What is a possible formula for this compound?A CaF2 B NaCl C SO2
D MgO [Nov-2013]85- Ionic compounds have high melting points
because of the strong attraction between oppositelycharged
ions.Which compound has the lowest melting point? C [Nov-2013]
PAPER-2 THEORY.1- Tritium is an isotope of hydrogen.An ion of
tritium has the following structure.
(a) Complete the following table to show the names and charges
of the particles in thistritium ion.
(b) Using the symbol T to represent tritium, give the formulae
of(i) the ion shown above
.................................................................................................(ii)
the compound formed between tritium and sodium.
................................................[2](c) Would you
expect the oxide of tritium to be a solid, a liquid or a
gas?Explain your
reasoning...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................[1][D02/q3]2-
The structures of two ionic lattices are shown below.
(a) Explain why these two solids do not conduct
electricity...........................................................................................................................................................................................................................................................................................................[1](b)
(i) Explain why magnesium oxide has a very high melting
point...........................................................................................................................................................................................................................................................................................................................................(ii)
Suggest why the melting point of magnesium oxide is much higher
than that ofsodium
chloride....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................[2]
(c) Draw the electronic structure of a magnesium ion and of an
oxide ion.magnesium ion
oxide ion
[2][June 2003/q7]3- The metal tungsten, symbol W, is used to
make wire filaments in light bulbs. The wire glowswhen electricity
passes through it.This is the structure of a typical metal
(a) Use this structure to explain how tungsten conducts
electricity.................................................................................................................................................................................................................................................................................[1](b)
Suggest two other physical properties of
tungsten.................................................................................................................................................................................................................................................................................[2](c)
In a light bulb, the tungsten wire may get so hot that it melts and
breaks.This graph shows the heating curve for tungsten.
(i) Use the graph to give the boiling point of
tungsten....................................................................................................................................(ii)
Predict the temperature when the tungsten wire
breaks................................................................................................................................[2][d
2003/q4]4- Sodium is stored under oil because it rapidly oxidises
to form sodium oxide, Na2O.(a) Draw a dot and cross diagram to show
the bonding in sodium oxide, Na2O. You needonly show outer shell
electrons.
[2]Sodium oxide reacts with water to form sodium hydroxide.(b)
Write an equation for this
reaction.......................................................................................................................................[1](c)
62 g of sodium oxide are used to make 2 dm3 of aqueous sodium
hydroxide.What is the concentration of the sodium hydroxide
solution? Answer .............................................
mol/dm3 [2][D 2003 /q6]