NECO Chemistry Practical Specimens for 2025/2026

NECO Chemistry Practical Specimens for 2025/2026 and NECO 2025/2026 MOCK CHEMISTRY PRACTICAL EXAMINATION

The NECO Chemistry Practical is a critical component of the Senior Secondary Certificate Examination (SSCE). The practical test is designed to assess students’ hands-on skills in Chemistry, including titration techniques, qualitative analysis, and understanding of chemical apparatus and reactions.

Official Instructions to Schools

1. Schools must ensure that each candidate receives a complete set of apparatus and chemicals.

2. All specimens must be prepared in advance and kept confidential until the date of the examination.

3. Each candidate’s set of materials must be clearly labeled with the candidate number and specimen code.

4. Each school should prepare a detailed Supervisor’s Report, including actual titration values for at least two candidates per session.

Apparatus and Reagents Required for Each Candidate

Each candidate should be provided with the following equipment and materials:

Apparatus

1. One 50 cm³ burette

2. One 20 cm³ or 25 cm³ pipette (all candidates must use the same size)

3. One pipette filler or teat

4. One retort stand with clamp

5. One white tile (for observing color change in titrations)

6. One conical flask (250 cm³)

7. Two clean beakers (100 cm³ each)

8. Test tubes (at least 5)

9. Test tube holder

10. One boiling tube

11. Filter paper

12. Glass rod

13. Wash bottle containing distilled water

14. Heat source (e.g., spirit lamp or Bunsen burner)

15. Funnel

16. Watch glass

17. Spatula

18. Red and blue litmus paper

19. Universal indicator or pH paper

20. Labels for all containers and solutions

NECO Chemistry Practical Specimens for 2025/2026 and NECO 2025/2026 MOCK CHEMISTRY PRACTICAL EXAMINATION

Reagents to Be Supplied

Each school should prepare and label the following standard reagents and specimens for each candidate:

Note: All containers should be properly labeled (e.g., A₁, B₁, C₁, etc.) to match candidate numbers.

Additional Chemicals for Qualitative Analysis

1. Dilute hydrochloric acid (HCl)

2. Dilute sodium hydroxide (NaOH)

3. Ammonia solution (NH₄OH)

4. Barium chloride (BaCl₂) solution

5. Silver nitrate (AgNO₃) solution

6. Distilled water

Structure of the Chemistry Practical Exam

The practical examination typically consists of two major tasks:

Task 1: Quantitative Analysis (Titration)

Candidates are required to:

1. Use a pipette to measure and deliver solution B into a conical flask.

2. Fill a burette with solution A.

3. Add solution A to solution B gradually while swirling, using a suitable indicator (usually methyl orange or phenolphthalein).

4. Determine the volume of A required to neutralize B.

5. Record burette readings, calculate the average titre, and perform stoichiometric calculations.

Expected Calculations:

1. Determination of concentration (mol/dm³)

2. Molar ratio interpretation

3. Balanced chemical equations

Task 2: Qualitative Analysis

Candidates are expected to:

1. Perform tests on solid C and other unknown solutions.

2. Record observations accurately (color changes, precipitate formation, gas evolution).

3. Infer the identity of ions present.

4. Write chemical equations for reactions observed.

Common Tests Include:

1. Flame test for metallic ions

2. Addition of NaOH or NH₄OH to detect metal cations

3. Reaction with dilute HCl to detect carbonates

4. Barium chloride test for sulphates

5. Silver nitrate test for halides

Teacher’s Role and Reporting

1. Each school must fill in a Chemistry Practical Supervisor’s Report, confirming the concentrations of solutions used.

2. The report should include the correct titre values obtained by at least two candidates.

3. Teachers must ensure that all candidates are provided with materials of consistent concentration and quantity.

4. Any deviation must be clearly documented.

Summary of Requirements

For Each Candidate:

1. A full set of labeled apparatus

2. Specimen solutions A, B, and solid C

3. Access to additional reagents for qualitative analysis

4. Proper guidance on laboratory safety and chemical handling

For the School:

1. Confidential preparation of all specimens and solutions

2. Accurate labeling and distribution

3. Supervisor’s Report filled and submitted alongside students’ scripts

Tips for Candidates

1. Revise titration techniques thoroughly and practice reading burettes and pipettes accurately.

2. Memorize color changes and solubility rules for cation and anion identification.

3. Know your indicators: methyl orange turns from orange to pink (acidic to alkaline), phenolphthalein goes from colorless to pink (alkaline).

4. Practice chemical equations related to reactions observed during tests.

5. Be neat and systematic in writing observations, inferences, and calculations.

NECO 2025/2026 MOCK CHEMISTRY PRACTICAL EXAMINATION

General Instructions

• Answer all questions.

• All necessary apparatus and chemicals will be provided.

• Record your observations carefully.

• All workings must be clearly shown.

Specimens Provided

Question 1: Quantitative Analysis (Titration)

You are provided with:

• Solution A: 0.10 mol/dm³ tetraoxosulphate(VI) acid

• Solution B: 0.05 mol/dm³ sodium carbonate

Using a pipette, measure 25.0 cm³ of solution B into a conical flask. Titrate it against solution A using methyl orange as indicator.

(a) Record the following:
i. Initial and final burette readings for three titrations
ii. Volume of acid used in each case
iii. Average volume used (titre)

(b) Write a balanced equation for the reaction.
(c) Calculate the number of moles of acid used.
(d) Determine the molar ratio and confirm if the given concentrations are correct.

Sample Data (For Practice Use)

Average titre = (24.50 + 24.60)/2 = 24.55 cm³

Balanced Equation:

H2SO4+Na2CO3→Na2SO4+H2O+CO2H_2SO_4 + Na_2CO_3 \rightarrow Na_2SO_4 + H_2O + CO_2H2​SO4​+Na2​CO3​→Na2​SO4​+H2​O+CO2​

Moles of Na₂CO₃ in 25.0 cm³ of B:

=25.01000×0.05=0.00125 mol= \frac{25.0}{1000} \times 0.05 = 0.00125 \text{ mol}=100025.0​×0.05=0.00125 mol

From the equation: 1 mole of H₂SO₄ reacts with 1 mole of Na₂CO₃.

So, moles of H₂SO₄ = 0.00125 mol
Concentration of H₂SO₄ = 0.00125×100024.55≈0.0509 mol/dm3\frac{0.00125 \times 1000}{24.55} \approx 0.0509 \, \text{mol/dm}^324.550.00125×1000​≈0.0509mol/dm3

NECO Chemistry Practical Specimens for 2025/2026 and NECO 2025/2026 MOCK CHEMISTRY PRACTICAL EXAMINATION

Diagram: Titration Setup

(Use an actual titration setup image in your print version)

Question 2: Qualitative Analysis

You are provided with solid C. Carry out the following tests and record your observations.

(a) Test the solubility of C in water.
(b) Add dilute HCl to a sample of C.
(c) To another portion of C, add distilled water, shake and divide into two:

• To one part, add NaOH dropwise and then in excess.

• To the second part, add NH₃(aq) dropwise and then in excess.

Expected Observations and Inferences

Confirmatory Test:
Add BaCl₂ to the solution from (a) — white precipitate forms, confirming sulphate if present.

Diagram: Qualitative Analysis Setup

(Insert diagram showing labeled test tubes, reagents, and expected reactions)

Marking Scheme

Question 1 – Titration (30 Marks)

Question 2 – Qualitative Analysis (40 Marks)

Practical Skills and Reporting (30 Marks)

1. Neat recording of data: 10 marks

2. Proper diagram labeling: 5 marks

3. Accuracy and completeness: 15 marks

Total: 100 Marks