IB Questionbank

User interface language: English | Español

Date	May 2021	Marks available	2	Reference code	21M.2.sl.TZ2.2
Level	SL	Paper	2	Time zone	TZ2
Command term	State	Question number	2	Adapted from	N/A

Question

The properties of elements can be predicted from their position in the periodic table.

Explain why Si has a smaller atomic radius than Al.

[2]

a(i).

Explain the decrease in radius from Na to Na⁺.

[2]

a(ii).

State the condensed electron configurations for Cr and Cr3⁺.

[2]

b(i).

Describe metallic bonding and how it contributes to electrical conductivity.

[3]

b(ii).

Deduce the Lewis (electron dot) structure and molecular geometry of sulfur dichloride, SCl₂.

[2]

Suggest, giving reasons, the relative volatilities of SCl₂ and H₂O.

[3]

Consider the following equilibrium reaction:

2SO₂(g) + O₂(g) $⇌$ 2SO₃(g)

State and explain how the equilibrium would be affected by increasing the volume of the reaction container at a constant temperature.

[3]

Markscheme

nuclear charge/number of protons/Z/Z_eff increases «causing a stronger pull on the outer electrons» ✓

same number of shells/«outer» energy level/shielding ✓

a(i).

Na⁺ has one less energy level/shell
OR
Na⁺ has 2 energy levels/shells AND Na has 3 ✓

less shielding «in Na⁺ so valence electrons attracted more strongly to nucleus»
OR
effective nuclear charge/Z_eff greater «in Na⁺ so valence electrons attracted more strongly to nucleus» ✓

Accept “more protons than electrons «in Na⁺»” OR “less electron-electron repulsion «in Na⁺»” for M2.

a(ii).

Cr:
[Ar] 4s¹3d⁵ ✓

Cr³⁺:
[Ar] 3d³ ✓

Accept “[Ar] 3d⁵4s¹”.

Accept “[Ar] 3d³4s⁰”.

Award [1 max] for two correct full electron configurations “1s²2s²2p⁶3s²3p⁶4s¹3d⁵ AND 1s²2s²2p⁶3s²3p⁶3d³”.

Award [1 max] for 4s¹3d⁵ AND 3d³.

b(i).

electrostatic attraction ✓

between «a lattice of» cations/positive «metal» ions AND «a sea of» delocalized electrons ✓

mobile electrons responsible for conductivity
OR
electrons move when a voltage/potential difference/electric field is applied ✓

Do not accept “nuclei” for “cations/positive ions” in M2.

Accept “mobile/free” for “delocalized” electrons in M2.

Accept “electrons move when connected to a cell/battery/power supply” OR “electrons move when connected in a circuit” for M3.

b(ii).

H₂O forms hydrogen bonding «while SCl₂ does not» ✓

SCl₂ «much» stronger London/dispersion/«instantaneous» induced dipole-induced dipole forces ✓

Alternative 1:
H₂O less volatile AND hydrogen bonding stronger «than dipole–dipole and dispersion forces» ✓

Alternative 2:
SCl₂ less volatile AND effect of dispersion forces «could be» greater than hydrogen bonding ✓\

Ignore reference to Van der Waals.

Accept “SCl₂ has «much» larger molar mass/electron density” for M2.

pressure decrease «due to larger volume» ✓

reactant side has more moles/molecules «of gas» ✓

reaction shifts left/towards reactants ✓

Award M3 only if M1 OR M2 is awarded.

Examiners report

[N/A]

a(i).

[N/A]

a(ii).

[N/A]

b(i).

[N/A]

b(ii).

[N/A]

Syllabus sections

Core » Topic 2: Atomic structure » 2.2 Electron configuration

Show 57 related questions

18M.1.sl.TZ1.6: Which are correct statements about the emission spectrum of hydrogen in the visible...
18M.2.sl.TZ1.2b:
State the electron configuration of the Ca²⁺ ion.
22M.2.hl.TZ1.6a(i): Draw arrows in the boxes to represent the electron configuration of a nitrogen atom.
18M.2.sl.TZ2.3c.i:
Copper is widely used as an electrical conductor.

Draw arrows in the boxes to represent the electronic configuration of copper in the 4s and 3d orbitals.
22M.2.sl.TZ2.2b(iii): Draw an arrow, labelled Z, to represent the lowest energy electron transition in the visible...
22M.2.sl.TZ1.2a: Draw arrows in the boxes to represent the electron configuration of a nitrogen atom.
19N.2.sl.TZ0.1c: Distinguish ultraviolet light from visible light in terms of wavelength and energy.
22M.1.sl.TZ1.6:
What is the maximum number of electrons that can occupy a p-orbital?

A. 2

B. 3

C. 6

D. 8
17M.1.sl.TZ1.6: Which electron transition in the hydrogen atom emission spectrum emits radiation with...
17M.2.sl.TZ2.1d:
Outline the model of electron configuration deduced from the hydrogen line emission spectrum (Bohr’s model).
19N.2.sl.TZ0.5a(i):
State the electron configuration of the Cu⁺ ion.
22M.2.sl.TZ2.2b(ii): Draw an arrow, labelled X, to represent the electron transition for the ionization of a...
18M.2.hl.TZ1.2c:
When calcium compounds are introduced into a gas flame a red colour is seen; sodium compounds give a yellow flame. Outline the source of the colours and why they are different.
17M.1.sl.TZ2.6: Which electron transition emits radiation of the longest wavelength?
22M.2.hl.TZ2.5a(i):
State the full electronic configuration of Fe²⁺.
16N.1.sl.TZ0.5: Which is correct for the line emission spectrum for hydrogen? A. Line M has a higher...
18M.2.sl.TZ1.2c:
When calcium compounds are introduced into a gas flame a red colour is seen; sodium compounds give a yellow flame. Outline the source of the colours and why they are different.
18N.1.sl.TZ0.5: Which statements are correct for the emission spectrum of hydrogen? I. The lines converge at...
18N.2.hl.TZ0.4a: Explain the decrease in atomic radius from Na to Cl.
18N.2.hl.TZ0.3a.ii:
Sketch the orbital diagram of the valence shell of a bromine atom (ground state) on the energy axis provided. Use boxes to represent orbitals and arrows to represent electrons.
18N.2.sl.TZ0.3a.ii:
Sketch the orbital diagram of the valence shell of a bromine atom (ground state) on the energy axis provided. Use boxes to represent orbitals and arrows to represent electrons.
17M.1.sl.TZ1.7: The full electron configuration of an element is: 1s22s22p63s23p2 To which group and period...
18N.2.hl.TZ0.3a.i:
State the electron configuration of a bromine atom.
18N.2.sl.TZ0.3a.i:
State the electron configuration of a bromine atom.
19M.1.hl.TZ1.4:
What is the ground state electron configuration of an atom of chromium, Cr (Z = 24)?

A. [Ar]3d⁶

B. [Ar]4s²3d⁴

C. [Ar]4s¹3d⁵

D. [Ar]4s²4p⁴
19M.2.hl.TZ1.6a:
Deduce the full electron configuration of Fe²⁺.
19M.1.sl.TZ2.6:
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
17N.2.hl.TZ0.2b: Outline how this spectrum is related to the energy levels in the hydrogen atom.
17N.1.sl.TZ0.6:
Which is the electron configuration of a chromium atom in the ground state?

A. [Ne]3s²3p⁶4s¹3d⁴

B. [Ar]3d³

C. 1s²2s²2p⁶3s²3p⁶4s²3d⁴

D. [Ar]4s¹3d⁵
17M.2.sl.TZ1.2d.i:
State the full electron configuration of the ${}_{22}^{48}{\text{Ti}}$ ²⁺ ion.
19N.1.sl.TZ0.6: Which represents the shape of an s atomic orbital?
16N.1.sl.TZ0.6:
What is the condensed electron configuration of the Fe²⁺ ion?

A. [Ar]3d⁶B. [Ar]3d⁴4s²C. [Ar]3d⁵4s¹D. [Ar]3d⁶4s²
16N.2.hl.TZ0.4c: Magnesium ions produce no emission or absorption lines in the visible region of the...
16N.2.hl.TZ0.4d:
(i) Explain the convergence of lines in a hydrogen emission spectrum.

(ii) State what can be determined from the frequency of the convergence limit.
21N.1.sl.TZ0.6: How many p-orbitals are occupied in a phosphorus atom? A. 2 B. 3 C. 5 D. 6
17N.2.sl.TZ0.2d: Describe the emission spectrum of hydrogen.
19M.1.sl.TZ1.6:
What is the ground state electron configuration of an atom of chromium, Cr (Z = 24)?

A. [Ar]3d⁶

B. [Ar]4s²3d⁴

C. [Ar]4s¹3d⁵

D. [Ar]4s²4p⁴
19N.2.hl.TZ0.6a(i):
State the electron configuration of the Cu⁺ ion.
18M.2.sl.TZ2.3a.i:
Draw the first four energy levels of a hydrogen atom on the axis, labelling n = 1, 2, 3 and 4.
21M.2.hl.TZ2.2b(iv):
[Cr(OH)₆]³⁻ forms a green solution. Estimate a wavelength of light absorbed by this complex, using section 17 of the data booklet.
18M.2.sl.TZ2.3a.ii:
Draw the lines, on your diagram, that represent the electron transitions to n = 2 in the emission spectrum.
22M.1.sl.TZ1.8:
Which of the following is the electron configuration of a metallic element?

A. [Ne] 3s² 3p²

B. [Ne] 3s² 3p⁴

C. [Ne] 3s² 3p⁶ 3d³ 4s²

D. [Ne] 3s² 3p⁶ 3d¹⁰ 4s² 4p⁵
22M.1.sl.TZ2.5: Which experimental results support the theory that electrons exist in discrete energy...
21M.1.sl.TZ1.6: Which represents a p orbital?
21N.2.hl.TZ0.9b(i):
Subsequent experiments showed electrons existing in energy levels occupying various orbital shapes.

Sketch diagrams of 1s, 2s and 2p.
21M.2.hl.TZ1.1d(iii):
State the full electron configuration of the sulfide ion.
21M.1.sl.TZ2.6: How are emission spectra formed? A. Photons are absorbed when promoted electrons return to...
21M.2.sl.TZ1.1c(ii):
State the full electron configuration of the sulfide ion.
21M.2.hl.TZ1.7b: Explain why there are frequencies of UV light that will dissociate O3 but not O2.
21M.2.hl.TZ2.2b(i):
State the condensed electron configurations for Cr and Cr3⁺.
20N.2.sl.TZ0.1a(i):
State the full electron configuration of the chlorine atom.
20N.1.sl.TZ0.6:
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.   $32$
20N.2.hl.TZ0.1a(i):
State the full electron configuration of the chlorine atom.
18M.2.hl.TZ2.3a.iv:
Calculate the wavelength, in m, for the electron transition corresponding to the frequency in (a)(iii) using section 1 of the data booklet.
21N.2.hl.TZ0.9b(ii):
State the electron configuration of copper.
21N.2.sl.TZ0.8b(ii):
State the electron configuration of copper.
21N.2.sl.TZ0.8b(i):
Subsequent experiments showed electrons existing in energy levels occupying various orbital shapes.

Sketch diagrams of 1s, 2s and 2p.

Hide related questions

Core » Topic 2: Atomic structure

Core

Question

Markscheme

Examiners report

Syllabus sections

View options