CHE2122 Chemistry - Exam Suggestion and Topic Frequency Analysis¶

Source basis: BOU CHE2122 Chemistry question papers from Terms 161, 171, 181, 201 and 211.
Important: This is an evidence-based suggestion from five supplied past papers, not a guarantee of the next examination. The frequency values describe past recurrence, not future probability.

How the ranking was calculated¶

A topic receives one occurrence when it appears at least once in a term.
Repeated subparts from the same term do not increase that topic's count.
Therefore, the maximum frequency is 5/5 terms.
Closely connected forms were grouped only when they test the same syllabus area. For example, semiconductor questions and valence/conduction/forbidden-band questions are grouped as Semiconductors and band theory.
The chart, topic labels, rankings and study priorities are analysis. The wording inside the question blocks is retained from the original papers.

Colorful topic-frequency graph¶

Color key¶

Red - Very high: appeared in 5 of 5 terms
Orange - High: appeared in 4 of 5 terms
Purple - Medium: appeared in 3 of 5 terms
Blue - Supporting: appeared in 2 of 5 terms

Complete ranked frequency table¶

Rank	Topic	161	171	181	201	211	Frequency
1	Aldol condensation / reaction	✓	✓	✓	✓	✓	5/5
1	Equilibrium, mass action and \(K_p\)-\(K_c\)	✓	✓	✓	✓	✓	5/5
1	Solutions, concentration and pH	✓	✓	✓	✓	✓	5/5
1	Semiconductors and band theory	✓	✓	✓	✓	✓	5/5
5	Orbitals, quantum numbers and electron configuration		✓	✓	✓	✓	4/5
5	Ionization energy and electron affinity	✓		✓	✓	✓	4/5
5	First-order reaction kinetics	✓	✓	✓	✓		4/5
5	Lewis, co-ordinate and covalent bonding	✓		✓	✓	✓	4/5
5	Carbonyl / alcohol / aldehyde / ketone	✓	✓	✓	✓		4/5
5	Cannizzaro reaction	✓		✓	✓	✓	4/5
11	Defects in solids		✓		✓	✓	3/5
11	Molecular orbital theory (MOT)			✓	✓	✓	3/5
11	Hydrogen bonding and water anomaly	✓	✓		✓		3/5
11	Isotopes, isobars and isotones		✓	✓		✓	3/5
11	Thermochemistry	✓	✓			✓	3/5
16	Phase rule and water phase diagram				✓	✓	2/5
16	Bohr and Rutherford atomic models	✓			✓		2/5
16	Noble gases		✓	✓			2/5
16	Raoult's law and colligative properties				✓	✓	2/5

Recommended study order¶

First priority: all four topics with 5/5 frequency.
Second priority: all six topics with 4/5 frequency.
Third priority: defects, MOT, hydrogen bonding, isotopes/isobars/isotones and thermochemistry.
Final coverage: phase rule, atomic models, noble gases, Raoult's law and colligative properties.

The safest practical approach is to prepare every question in the Core seven-question suggestion, then use the High-value backup questions to cover alternative wording and omitted subtopics.

Core Seven-Question Suggestion¶

Each block below is one complete 14-mark question taken from an original past paper. Original question numbers and subpart labels are retained, even though the blocks come from different terms.

Core 1 - Atomic Structure and Periodicity¶

Source: 211 Term, Question 2

2.¶

(a) Write down the ground state electron configuration of the following elements:

(i) C(6); (ii) S(16); (iii) Mo(42); (iv) Ni(28); (v) Na(11).
Marks: 5

(b) What is ionization energy? Why does the ionization energy decrease down a group in the periodic table?
Marks: 2+4

(c) Why is the electron affinity of Be negative?
Marks: 3

Core 2 - Chemical Kinetics¶

Source: 181 Term, Question 2

2.¶

(a) What is the rate of reaction?
Marks: 3

(b) Describe the equation to calculate the rate constant of a 1st order reaction and show the half-life of a 1st order reaction is independent of initial concentration of reactants.
Marks: 4+3

(c) Compared A decomposes to form B and C, the reaction is 1st order, A \(25^\circ\text{C}\) the rate constant for the reaction is \(0.45\text{s}^{-1}\). What is the half-life of A at \(25^\circ\text{C}\)?
Marks: 4

Core 3 - Chemical Bonding and Molecular Orbital Theory¶

Source: 211 Term, Question 3

3.¶

(a) How many types of overlapping of covalent bonds are seen?
Marks: 4

(b) Define co-ordination covalent bond. Show every type of bond available in \(\mathrm{NH_4Cl}\).
Marks: 2+3

(c) Draw and explain the molecular orbitals of \(\mathrm{O_2}\) according to MOT.
Marks: 5

Core 4 - Chemical Equilibrium¶

Source: 211 Term, Question 5

5.¶

(a) What is an equilibrium constant? Write down the characteristics of chemical equilibrium.
Marks: 1+4

(b) Show the relation between \(K_p\) and \(K_c\).
Marks: 5

(c) Calculate the concentration of \(\mathrm{OH^-}\) ions from water at \(298\text{K}\) in \(0.02\text{M HCl}\) solution.
Marks: 4

Core 5 - Solutions and pH¶

Source: 181 Term, Question 6

6.¶

(a) Explain the terms: (i) Normality; (ii) Molarity and (iii) Molality of a solution.
Marks: 6

(b) Calculate the normality and molarity of a solution containing \(20.7\text{g}\) of \(\mathrm{K_2CO_3}\) dissolved in \(500\text{ml}\) of the given solution.
Marks: 4

(c) What is meant by \(\mathrm{p^H}\)? Calculate the \(\mathrm{p^H}\) of \(0.001\text{N HCl}\) assuming complete ionization of HCl.
Marks: 1+3

Core 6 - Phase Rule, Semiconductors and Defects in Solids¶

Source: 211 Term, Question 6

6.¶

(a) What is phase rule? Draw a phase diagram of water.
Marks: 2+3

(b) What are conductor and semiconductor?
Marks: 2+2

(c) How many types of defects are available in solid? Explain point defect with suitable example.
Marks: 2+3

Core 7 - Selective Organic Reactions and Thermochemistry¶

Source: 211 Term, Question 7

7.¶

(a) What are the IUPAC names of the following compounds;
Marks: 4

(b) Write down the following organic reactions:

Aldol reaction, Cannizzaro reaction and Grignard reaction
Marks: 6

(c) Write the laws of thermochemistry.
Marks: 4

High-Value Backup Questions¶

These blocks cover important alternative forms that are not fully represented in the core seven.

Backup 1 - Atomic Models and Quantum Numbers¶

Source: 201 Term, Question 1

1.¶

(a) Describe Rutherford's atomic model and mention its weakness.
Marks: 6

(b) Write down postulates of Bhor's theory.
Marks: 4

(c) Find out the number of orbital's for which the following sets of quantum numbers is possible \(n=3\), \(l=2\) and \(m=(\pm2)\).
Marks: 4

Backup 2 - Bonding, Water Anomaly and Phase Diagram¶

Source: 201 Term, Question 4

4.¶

(a) Compare the properties of ionic and covalent compounds.
Marks: 4

(b) Explain the following terms:

    (i) Hydrogen bonding;
    (ii) Metallic bonding;
    (iii) Water has maximum density at \(4^\circ\text{C}\).
Marks: 3x2

(c) Draw the phase diagram of the water system and find the degrees of freedom in every region of this diagram.
Marks: 4

Backup 3 - Defects, Hydrogen Bonding and Isotopes¶

Source: 171 Term, Question 5

5.¶

(a) What are defects in solid/crystal? Write some importance of crystal defects.
Marks: 2+2

(b) How many types of imperfections in crystalline solids? Give their names and explain point defects with suitable example.
Marks: 3+3

(c) Show the hydrogen bonding in acetic acid molecules and find Isotope, Isobar, Isotone from the following atoms \({}^{14}_{6}\mathrm{C}\), \({}^{32}_{14}\mathrm{Si}\), \({}^{127}_{53}\mathrm{I}\) and \({}^{16}_{8}\mathrm{O}\).
Marks: 4

Backup 4 - Noble Gases, Hydrogen Bonding and pH Scale¶

Source: 171 Term, Question 7

7.¶

(a) Write short notes on the followings

    (i) Noble gasses;
    (ii) Hydrogen bonding;
    (iii) Normality and pH of solutions;
    (iv) Diamagnetism and paramagnetism.
Marks: 12

(b) Show how the \(\mathrm{p^H}\) scale was established from 'onic product of water.
Marks: 2

Backup 5 - First-Order Reaction, Raoult's Law and Concentration¶

Source: 201 Term, Question 6

6.¶

(a) Derive mathematical expression for the rate constant of a reaction (\(A\longrightarrow\) Products) of the first order.
Marks: 4

(b) State and derive the Raoult's law for dilute solution.
Marks: 7

(c) \(5.3\text{ g}\) of \(\mathrm{Na_2CO_3}\) is dissolved in \(1\text{ Kg}\) of water. If the density of the solution is \(0.997\text{gmL}^{-1}\). Calculate the molarity and normality of the solution.
Marks: 3

Final Revision Checklist¶

[ ] Aldol, Cannizzaro and Grignard reactions
[ ] Equilibrium constant, characteristics and \(K_p\)-\(K_c\) relation
[ ] Normality, molarity, molality and pH numericals
[ ] Semiconductor, band theory and point defects
[ ] Electron configuration, ionization energy and electron affinity
[ ] First-order rate equation and half-life
[ ] Co-ordinate/covalent bonding and \(\mathrm{O_2}\) MOT
[ ] Phase rule and water phase diagram
[ ] Thermochemistry laws
[ ] Original structural formulae in Question 7(a)