IB Chemistry SL Classified Paper_1 Chapter_2
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IB Chemistry SL Classified Paper_1 Chapter_2
SPECIMEN 2016 Q (5, 6, 7)
1) 5. Which electronic transition would absorb the radiation of the shortest
wavelength?
2) 6. What are the numbers of protons, neutrons and electrons in the ion
238 2+
92 X
Protons Neutrons Electrons
A. 146 92 146
B. 92 146 90
C. 92 146 94
D. 92 238 90
3) 7. Which element is in the f-block of the periodic table?
A. Be
B. Ce
C. Ge
D. Re
May 2016 TZ0 Q (5, 6, 7)
53
4) 5. Which is correct for the chromium isotope 24 Cr ?
A. 24 neutrons and 53 nucleons
B. 24 protons and 29 nucleons
C. 24 protons and 29 neutrons
D. 24 electrons and 53 neutrons
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IB Chemistry SL Classified Paper_1 Chapter_2
5) 6. Which electron configuration is correct for the selenide ion, Se2−?
A. 1s2 2s2 2p6 3s2 3p6 4s2 4d10 4p4
B. 1s2 2s2 2p6 3s2 3p6 4s2 4d10 4p6
C. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p4
D. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
6) 7. Which element is a metalloid?
A. Co
B. As
C. Cs
D. Es
Nov 2016 TZ0 Q (5, 6)
7) 5. Which is correct for the line emission spectrum for hydrogen?
A. Line M has a higher energy than line N.
B. Line N has a lower frequency than line M.
C. Line M has a longer wavelength than line N.
D. Lines converge at lower energy.
8) 6. What is the condensed electron configuration of the Fe2+ ion?
A. [Ar] 3d6
B. [Ar] 3d4 4s2
C. [Ar] 3d5 4s1
D. [Ar] 3d6 4s2
May 2017 TZ1 Q (5, 6, 7)
9) 5. In which set do all the species contain more electrons than neutrons?
A. 14N, 16O, 11C
B. 14N, 16O, 11C4–
C. 14N3–, 16O2–, 11C
D. 14N3–, 16O2–, 11C4+
25 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
10) 6. Which electron transition in the hydrogen atom emission spectrum
emits radiation with the longest wavelength?
A. n = 2 → n = 1
B. n = 1 → n = 2
C. n = 4 → n = 1
D. n = 3 → n = 2
11) 7. The full electron configuration of an element is:
1s2 2s2 2p6 3s2 3p2
To which group and period does the element belong?
Group Period
A. 2 3
B. 3 2
C. 3 4
D. 14 3
May 2017 TZ2 Q (5, 6)
24
12) 5. What does 12 Mg2+ represent?
A. An ion with 12 protons and 24 neutrons
B. An ion with 14 protons and 24 neutrons
C. An ion with 12 protons and 12 neutrons
D. An ion with 12 protons and 22 neutrons
13) 6. Which electron transition emits radiation of the longest wavelength?
26 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
Nov 2017 TZ0 Q (5, 6)
14) 5. What is the number of protons and the number of neutrons in 131I?
15) 6. Which is the electron configuration of a chromium atom in the ground
state?
A. [Ne] 3s2 3p6 4s1 3d4
B. [Ar] 3d3
C. 1s2 2s2 2p6 3s2 3p6 4s2 3d4
D. [Ar] 4s1 3d5
May 2018 TZ1 Q (5, 6)
16) 5. Which shows the number of subatomic particles in 31P3−?
17) 6. Which are correct statements about the emission spectrum of hydrogen
in the visible region?
I. The red line has a lower energy than the blue line.
II. The lines converge at longer wavelength.
III. The frequency of the blue line is greater than the frequency of the red
line.
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
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IB Chemistry SL Classified Paper_1 Chapter_2
May 2018 TZ2 Q (5, 6)
18) 5. What is the composition of the nucleus of 26Mg?
19) 6. Which electron transition emits energy of the longest wavelength?
Nov 2018 TZ0 Q (5, 6)
20) 5. Which statements are correct for the emission spectrum of hydrogen?
I. The lines converge at higher frequencies.
II. Electron transitions to n = 2 are responsible for lines in the visible region.
III. Lines are produced when electrons move from lower to higher energy
levels.
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
21) 6. Which statement about 56Fe3+ and 54Fe2+ is correct?
A. Both have the same numbers of protons and electrons.
B. Both have the same number of protons.
C. Both have the same number of neutrons.
D. Both have the same numbers of protons and neutrons.
28 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
May 2019 TZ1 Q (5, 6)
22) 5. Bromine consists of two stable isotopes that exist in approximately a 1 :
1 ratio. The relative atomic mass, Ar, of bromine is 79.90. Which are the
stable isotopes of bromine?
23) 6. What is the ground state electron configuration of an atom of
chromium, Cr (Z = 24)?
May 2019 TZ2 Q (5, 6)
24) 5. Which is correct for 34
16 S2−
25) 6. Which transition in the hydrogen atom emits visible light?
A. n = 1 to n = 2
B. n = 2 to n = 3
C. n = 2 to n = 1
D. n = 3 to n = 2
29 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
Nov 2019 TZ0 Q (5, 6)
26) 5. What is represented by A in A
Z X2− ?
A. Number of electrons
B. Number of neutrons
C. Number of nucleons
D. Number of protons
27) 6. Which represents the shape of an s atomic orbital?
Nov 2020 TZ0 Q (5, 6)
28) 5. What is the relative atomic mass, Ar, of an element with this mass
spectrum?
A. 24.0
B. 24.3
C. 24.9
D. 25.0
29) 6. What is the maximum number of electrons that can occupy the 4th
main energy level in an atom?
A. 8
B. 14
C. 18
D. 32
30 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
May 2021 TZ1 Q (5, 6, 7)
30) 5. What is the relative molecular mass of bromine, according to the
following mass spectrum?
31) 6. Which represents a p orbital?
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IB Chemistry SL Classified Paper_1 Chapter_2
32) 7. Which species has the same electron configuration as argon?
A. Br−
B. Ca2+
C. Al3+
D. Si4+
May 2021 TZ2 Q (5, 6)
33) 5. What is represented by “2–" in AZ X 2−
A. loss of electron
B. gain of electron
C. loss of proton
D. gain of proton
34) 6. How are emission spectra formed?
A. Photons are absorbed when promoted electrons return to a lower energy
level.
B. Photons are absorbed when electrons are promoted to a higher energy
level.
C. Photons are emitted when electrons are promoted to a higher energy level.
D. Photons are emitted when promoted electrons return to a lower energy
level.
Nov 2021 TZ0 Q (5, 6)
35) 5. Consider the mass spectrum of an element:
What is the relative atomic mass of this element?
A. 10.2
B. 10.5
C. 10.8
D. 10.9
32 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
36) 6. How many p-orbitals are occupied in a phosphorus atom?
A. 2
B. 3
C. 5
D. 6
May 2022 TZ1 Q (5, 6)
37) 5. Naturally occurring gallium consists of the isotopes 71Ga and 69Ga.
What is the approximate percentage abundance of 69Ga?
Mr (Ga) = 69.72.
A. 40 %
B. 50 %
C. 60 %
D. 75 %
38) 6. What is the maximum number of electrons that can occupy a p-orbital?
A. 2
B. 3
C. 6
D. 8
May 2022 TZ2 Q (5, 6)
39) 5. Which experimental results support the theory that electrons exist in
discrete energy levels?
A. 1H NMR
B. X-ray diffraction pattern
C. Emission spectra
D. IR spectra
33 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
40) 6. What is the relative atomic mass of an element with the following mass
spectrum?
A. 23
B. 24
C. 25
D. 28
Nov 2022 TZ0 Q (5, 6)
41) 5. Which quantities are different between two species represented by the
128 −
notation 128
52 Te and 53 I ?
A. The number of protons only
B. The number of protons and electrons only
C. The number of protons and neutrons only
D. The number of protons, neutrons and electrons
42) 6. What is the relative atomic mass of a sample of chlorine containing
70% of the 35Cl isotope and 30% of the 37Cl isotope?
A. 35.4
B. 35.5
C. 35.6
D. 35.7
34 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
May 2023 TZ1 Q (5, 6)
43) 5. What is the maximum number of electrons in energy level n = 4?
A. 8
B. 18
C. 32
D. 50
44) 6. What are the numbers of neutrons and electrons in 32
16 S2− ?
May 2023 TZ2 Q (5, 6, 7)
45) 5. What is the correct ground state electron orbital configuration for
2s22p2?
35 2 – Atomic Structure Mostafa Barakat (0100 165 44 62)
IB Chemistry SL Classified Paper_1 Chapter_2
46) 6. The following diagram shows a light passing through a cold gas cloud,
and light from a hot gas cloud.
Which types of spectra are associated with light passing through a cold gas
cloud, Spectrum A, and light from a hot gas cloud, Spectrum B?
Spectrum A Spectrum B
A. Absorption Emission
B. Emission Absorption
C. Absorption Absorption
D. Emission Emission
47) 7. What is the electron configuration for an element in group 4 period 5?
A. [Kr] 5s2 4d2
B. [Ar] 4s2 3d2
C. [Ar] 4s2 3d10 4p3
D. [Kr] 5s2 4d10 5p2
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