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El- Waha language schools
Chemistry Department
American Diploma(11)
1
Type One
Choose the correct answer as a , b , c or d in the answer sheet :
1) The number of electrons required to fill the fourth energy level (N) is ..............
1) 8
2) 18
3) 32
4) 72
2) The number of orbitals in the sublevel 3d is .....................
1) five
2) six
3) seven
4) four
3) The maximum number of energy levels in the heaviest known atoms in its normal state
is .........................
1) five
2) six
3) seven
4) eight
4) Number of orbitals in sublevel 4f is ........................
1) 3
2) 4
3) 5
4) 7
5) The third energy level (M) of an atom is saturated with a number of electrons that equals
....................................
1) 18
2) 8
3) 32
4) 50
6) The number which indicates the principal energy level in an atom is the ............ ........
quantum number.
1) magnetic
2) subsidiary
3) principal
4) spin
7) The magnetic quantum number defines ........................
1) the type of electron movement around its axis.
2) the number of electrons in the sublevel.
3) the number of sublevels in the principal level.
4) the number of orbitals in the sublevel.
8) According to Hund's rule , the electronic configuration in the last energy levels of nitrogen
atom 7N is .............................
9) If an atom is transfered from an energy level near the nucleus to far one , it ............
1) loses a quantum of energy
2) gains a quantum of energy
3) radiates a light ray
4) does not lose a part of its energy
10) The number of orbitals in the principal energy level (n) is .......................
1) 2n
2) 2n2
3) n2
4) n-2
2
11) The sublevel (p) is .....................................
1) a symmetrical sperical obital
3) three orbitals similar in shape and energy
2) five orbitals
4) seven orbitals
12) By using quantum mechanics .................... identified to the uncertainity principle
1) Schrodinger
2) Sommerfield
3) Heisenberg
4) Plank
13) The most important modifications on the atomic model of “Bohr” are ......................
1) the dual nature of the electron
2) the uncertainity principle
3) finding the suitable equation which describes the wave motion of the electron
4) all the previous
14) Atoms of all elements do not contain the energy sublevel ......................
1) 4d
2) 3s
3) 2d
4) 2p
15) The number of orbitals in sublevel 5f is ................................
1) 3
2) 5
3) 7
4) 14
16) The oxidation number of hydrogen in LiH is ...........................
1) +1
2) –1
3) +2
4) –2
17) The oxidation number of nitrogen in hydroxylamine NH2OH is .......................
1) –1
2) +1
3) +2
4) –2
18) The d-block elements are called ....................
1) representative elements
3) noble gases
2) transition elements
4) actinides
19) The oxidation number of sulphur in Na2S2O3 compound is ..................
1) +2
2) –4
3) +5
4) –6
20) Elements in which their (d) sublevel orbitals are gradually filled with electrons are called
..................... elements
1) transition
2) representative
3) inner transition
4) noble
21) The electronic configuration of the outermost orbitals of an element is 5f 3 , 6d1 , 7s2 . This
element is one of the ................. series
1) first transition
2) inner transition ( actinides )
3) inner transition ( lanthanides )
4) third transition
22) If the bond length in the chlorine molecule is 1.98 A and the bond length between carbon and
chlorine atoms equals 1.76 A , then the atomic radius of carbon atom equals ............
1) 0.12 Ao
2) 1.1 Ao
3) 0.77 Ao
4) 3.74 Ao
23) In the actinides series , the sublevel ............... is filled successively by electrons
1) 3d
2) 4d
3) 4f
4) 5f
24) The oxidaion number of oxygen in the hydrogen peroxide is .....................
1) –2
2) +2
3) +1
4) –1
3
25) The element of electronic configuration Xe(54) 6s2 5d1 4f3 , represents ....................
1) second transition series
2) third transition series
3) lanthanide series
4) actinide series
26) The oxidation number of chlorine in KClO4 compound is ......................
1) –1
2) +7
3) –7
4) +1
27) The oxidation number of Cr in ( Cr2O7 )-2 is .......................
1) +6
2) –6
3) +3
4) -3
28) The chemical formula of calcium phosphate is …………………….
1) Ca3(PO4)2
2) K3PO4
3) CaPO4
4) Ca2(PO4)3
29) The molecular formula of a compound having emperical formula C2H5ON is …………….
1) CH5ON
2) C4H10O2N2
3) CHON
4) C6H10N2O2
30) The valency of an element is …………………………..
1) the number of electrons lost
2) the number of electrons gained
3) the number of electrons shared
4) all the above
Type Two
Write the scientific concept for each of the following sentences :
1) The amount of energy absorbed or emitted when an electron jumps from one energy level
to another .
………………………………
2) The principle which states that “ no electron pairing takes place in a given sublevel until
each orbital contains one electron”
……………………………
3) The quantum number that defines the orbitals of a given energy sublevel and their
orientation in space .
………………………………
4) Number of electrons or number of protons in an atom.
…………………………….
5) Electrons occupy the orbitals in the order of increasing orbital energy, lowest energy orbitals
are filled first.
……………………………..
6) A number which defines the sublevels within a certain energy level.
………………………………
7) The process of losing electrons with the increase of positive charge.
……………………….
8) The quantity of energy required to remove the least bounded electrons from a single atom
in the gaseous state.
…………………………..
4
9) The tendency of an atom to attract the electrons of the chemical bond to itself.
……………………….
10) Half the distance between the two centers of the two similar atoms in a diatomic molecule
…………………………………
11) A series of elements in which the 5f sublevel is filled successively by electrons.
……………………………….
12) A group of elements whose valency shell generally has more than half its capacity of
electrons
……………………………….
13) A number that refers to the electric charge ( positive or negative ) that the atom would have
in the compound , if ionic or covalent
…………………………………..
14) The elements of the f-block , where the f-sublevels of these elements are successively filled
by electrons
…………………………
15) The number of electrons lost , gained or shared by an atom in a chemical reaction .
……………………………………….
16) The amount of energy required to remove electron from the positive ion M+ .
…………………………………..
17) Energy sublevel contains five orbitals .
…………………………..
18) The electron is negatively charged particle which also has wave properties.
………………………….
2
6
19) Elements having electronic configuration ends by ns np
…………………………..
20) Elements having ionic radius smaller than their atomic radius ……………………….
Type Three
Complete the following sentences with the suitable words or phrases :
1) ………………. used the quantum mechamics to conclude the uncertainity principle.
2) ……………….. states that “ pairing of electrons in any subshell does not take place
unless each orbital is firstly occupied by a single electron “.
3) The mathematical expression 2n2 defines the …………………… which can occupy
the energy level (n)
4) When an electron from the energy level (K) is transfered to the energy level (N) , it
absorbs an amount of energy called ……………..
5
5) Subsidiary quantum number defines the ………………………. in an atom which are
assigned by the symbols …………………
6) The ………… is spherical symmetrical in shape , while p orbital has ………… shape.
7) The element with electronic configuration 1s2 , 2s2 , 2p6 , 3s1 is present in the ………
group and the ………. period in the periodic table .
8) The oxidation number of oxygen in hydrogen peroxide is ….…… , and the oxidation
number of oxygen in the water molecule H2O is ………… .
9) The oxidation number of hydrogen in sodium hydride is ………… and the oxidation
number of hydrogen in HCl is ……………
10) Atomic radius is defined as ……….. the distance between the centres of two similar atoms
in a diatomic molecule
11) Oxidation number of manganese in KMnO4 compound is ……………. .
.
12) The oxidation number of oxygen in ozone molecule is ……………
13) In the periods , the values of ionization potential …………… as we go to the right
i.e as the atomic radius ………………
14) Representaive elements are of s and p-blocks except ……………………
15) Elements which fill 4f sublevel by electrons successively are ………………..
16) Periodic table consists of seven ……………….. and …………….. vertical groups .
Type Four
Give reasons for each of the following
1) Although the two electrons of the same orbital carry the same negative charge , they never
repel each other .
2) The spectral lines are essential characteristic for each element .
3) The sublevel s is saturated with two electrons , whereas the sublevel p is saturated with
six electrons .
4) Electrons prefered to occupy alone one orbital before pairing can take place in a given
sublevel .
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5) The matter waves associated with the wave motion differ from the electromagnetic waves
6) Sublevel 4s is filled with electrons before sublevel 3d .
7) The spin of single electons must be in the same direction .
8) The correct distribution of electrons in the last energy level of oxygen atom 8O is :
2s2 , 2px2 , 2py1 , 2pz1 and not 2s2 , 2px2 , 2py2 , 2pz0
9) The first ionization energy of noble gases of group zero is very high .
10) Atomic radii increase in the same group with the increase in the atomic number .
11) The ionization potential of magnesium ( 12Mg ) is less than the ionization potential of
chlorine ( 17Cl ) .
12) The radius of nonmetal ion is lager than that of the corresponding atom , while the radius
of the metal ion is smaller than that of the corresponding atom .
13) The bond length of iron III chloride molecule is shorter than the bond length of iron II
chloride molecule .
14) The values of atomic radii decrease as we go from left to right in the horizontal periods .
15) The second ionization potential of magnesium 12Mg is much lower than that of the 1st
ionization potential .
Type Five
Miscellaneous questions :
A) What is meant by :
1) Aufbau principle : …………………………………………………………………………….
…………………………………………………………………………….
2) Hund’s rule :
…………………………………………………………………………….
………………………………………………………………………………….
3) The quantum : ………………………………………………………………………………..
………………………………………………………………………………..
4) The dual nature of the electron : …………………………………………………………….
……………………………………………………………………………………..
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5) Electronegativity : ……………………………………………………………………………
………………………………………………………………………….
6) Oxidation number : …………………………………………………………………………..
………………………………………………………………………………
7) Reduction : …………………………………………………………………………………….
……………………………………………………………………………………
B) Write the electronic configuration of the following atoms :
a)
36Kr
b) 20Ca
c) 14Si
d) 11Na
C) Calculate the oxidation number of :
1) Sulphur in H2S
2) Nitrogen in NO2
3) Manganese in MnO44) Chromium and iron in the equation :
K2Cr2O7 + 6 FeCl3 + 14 HCl
2KCl + 2CrCl3 + 6 FeCl3 + 7 H2O
5) Chlorine in ClO3
6) Sulphur in S2O3
7) Chlorine in HClO4
8) Chromium in ( Cr2O7 )-2
D) The bond length between the chlorine atoms in the molecule ( Cl2 ) equals 1.98 A and the
bond length between carbon and chlorine atoms ( C—Cl ) equals 1.76 A . Calculate the
atomic radius of carbon atom .
8
E) Write the electronic configuration of an element with atomic number 14 . Define its block,
period and group in the periodic table .
F) Calculate the bond length in fluorine molecule provided that the bond length in hydrogen
fluoride molecule is 0.94 A and the bond length in hydrogen molecule is 0.6 A .
G) Determine the trend of the following properties in the periodic table :
…………….
…………………
Period
Period
Ionization energy
Atomic radius
Group
Group
………………
Period
Electronegativity
Group
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Type Six
Put right or wrong mark and correct the wrong sentences :
1) Schrodinger used the quantum mechamics to conclude the uncertainity principle.
2) De Broglie Principle states that “ pairing of electrins in any subshell does not take place
unless each orbital is firstly occupied by a single electron “.
3) The mathematical expression 2n2 defines the subsidiary quantum levels which can occupy
the energy level (n)
4) When an electron from the energy level (K) is transfered to the energy level (N) , it absorbs
an amount of energy equals three quanta .
5) Subsidiary quantum number defines the principal energy levels in an atom which are
assigned by the symbols K,L,M,......... .
6) The d orbital is spherical symmetrical in shape , while p orbital has an elliptical shape.
7) When an excited electron returns back to its original level it gains a quantum of energy
and the atom becomes excited atom .
8) The element with electronic configuration 1s2 , 2s2 , 2p6 , 3s2 is present in the period two and
the group three in the periodic table .
9) The oxidation number of oxygen in hydrogen peroxide is –2 , and the oxidation number
of phosphorus in the phosphorus molecule P4 is +4 .
10) The oxidation number of hydrogen in sodium hydride is +1 and the oxidation number of
oxygen in potassium superoxide is –1 .
11) Atomic radius is defined as the double distance between the centres of two similar atoms
in a diatomic molecule .
12) Oxidation number of manganese in KMnO4 compound is –6 .
13) The oxidation number of oxygen in ozone molecule is –3 .
14) The number representing the electric charge that the ion or atom in the compound
would have , be ionic or covalent , is called oxidation potential .
15) In the periods , the values of ionization potential increases as we go to the right i.e as the
atomic radius increases .
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Key Answer
Type One
Answer Sheet
1
1
2
3
4
16
1
2
3
4
2
1
2
3
4
17
1
2
3
4
3
1
2
3
4
18
1
2
3
4
4
1
2
3
4
19
1
2
3
4
5
1
2
3
4
20
1
2
3
4
6
1
2
3
4
21
1
2
3
4
7
1
2
3
4
22
1
2
3
4
8
1
2
3
4
23
1
2
3
4
9
1
2
3
4
24
1
2
3
4
10
1
2
3
4
25
1
2
3
4
11
1
2
3
4
26
1
2
3
4
12
1
2
3
4
27
1
2
3
4
13
1
2
3
4
28
1
2
3
4
14
1
2
3
4
29
1
2
3
4
15
1
2
3
4
30
1
2
3
4
Type Two
1.Quantum
3.Magnetic quantum number
5.Aufbau principle
7.Oxidation
9.Electronegativity
11.Inner transition elements (Actinides)
13.Oxidation number
15.Valency
17.d-sublevel
19.Noble gases
2.Hund’s rule
4.Atomic number
6.Subsidiary quantum number
8.Ionization energy
10.Atomic radius
12.Non-metals
14.Inner transition elements
16.2nd ionization energy
18.Dual nature of electron
20.Metals
11
Type Three
1. Heisenberg
3. The number of electrons
5. Energy sublevels…… s p d f
7. 1st group(IA) …… 3rd period
9. –1 ………….+1
11. +7
13. Increases ……..decreases
15. Inner transition elements ( lanthanides)
2. Hund’s rule
4. Quantum
6. S-orbital ………dumbell shape
8. –1 …………. –2
10. half
12. Zero
14. Noble gases
16. Periods …………. 18 columns
Type Four
3) because each orbital is occupied by two electrons . S orbital consists of one orbital and
P orbital consists of 3 orbitals
6) because 4s has lower energy than 3d
9) because noble gases have their outermost energy level completely filled ( stable ) , So it’s
difficult to remove electron from them
11) because chlorine has greater nuclear charge than magnesium so attract its electrons
more strongly and so its radius decreases
14) because the nuclear charge increases as we go from left to right so attract the outermost
electrons strongly and so volume decrease
Type Five
1st)
2nd)
Revise your sheets
a) 36Kr : 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
b) 20Ca : 1s2 2s2 2p6 3s2 3p6 4s2
c) 14Si : 1s2 2s2 2p6 3s2 3p2
d) 11Na : 1s2 2s2 2p6 3s1
12
C) 1) ( 2 X +1 ) + S = zero
so, S = -2
2) +4
3) +7
4) Cr : +6
+3
Fe : +2
5) +5
6) +2
7) +7
8) 2Cr + ( 7 x –2 ) = -2
2 Cr = 14 –2 = 12
+3
so, Cr = +6
D) atomic radius of chlorine = 1.98 / 2 = 0.99 Ao
atomic radius of carbon = 1.76 – 0.99 = 0.77 Ao
E) 14X : 1s2 2s2 2p6 3s2 3p2
Block : p
Period : 3
Group : 4A
F) atomic radius of hydrogen = 0.6 / 2 = 0.3 Ao
Atomic radius of fluorine = 0.94 – 0.3 = 0.64 Ao
Bond length of fluorine = 2 X 0.64 = 1.28 Ao
G) Revise your sheets
Type Six
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
wrong …….
wrong …….
wrong …….
wrong …….
wrong …….
wrong …….
wrong …….
wrong …….
wrong …….
wrong ……
11) wrong ……
12) wrong …….
13) wrong …….
14) wrong …….
15) wrong …….
Heisenberg
Hund’s rule
defines the number of electrons which occupy the energy level
one quantum
principal quantum number
s orbital , p orbital has dumbell shape
it emits energy and the atom becomes stable
period three , group 2A
–1 , zero
-1 , - ½
half the distance
+7
zero
called “oxidation number “
atomic radius decreases
13