NECO 2026 Chemistry Practical Questions and Answers
Instructions to Candidates
- Answer all questions.
- Read the instructions carefully before starting.
- Show all calculations.
- Write balanced chemical equations where necessary.
- Time Allowed: 2 Hours 30 Minutes.
- Total Marks: 60.
Specimens
You are provided with the following:
Specimen A
0.100 mol dm⁻³ Hydrochloric Acid (HCl)
Specimen B
0.100 mol dm⁻³ Sodium Hydroxide Solution (NaOH)
Specimen C
Unknown Salt Solution (containing Cu²⁺)
Specimen D
Unknown Salt Solution (containing Fe²⁺)
Specimen E
Specimen F
Dilute Sodium Hydroxide
Specimen G
Barium Chloride Solution
Specimen H
Dilute Nitric Acid
QUESTION 1 – Volumetric Analysis
Procedure
Pipette 25.0 cm³ of solution B into a conical flask.
Titrate against solution A using methyl orange indicator.
Record your readings.
Table of Readings
| Titration | Final (cm³) | Initial (cm³) | Titre (cm³) |
|---|---|---|---|
| Rough | 24.80 | 0.00 | 24.80 |
| 1st | 25.00 | 0.00 | 25.00 |
| 2nd | 24.95 | 0.00 | 24.95 |
| 3rd | 25.05 | 0.00 | 25.05 |
Average Titre = 25.00 cm³
(a) Write the balanced equation.
Answer:
HCl + NaOH → NaCl + H₂O
(b) Calculate the concentration of HCl.
Since:
25.0 cm³ NaOH reacts with 25.0 cm³ HCl
The mole ratio is 1 : 1
Concentration of HCl = 0.100 mol dm⁻³
(c) Calculate the number of moles of HCl used.
For molarity calculations:
Volume = 25.0 cm³ = 0.025 dm³
Moles = 0.100 × 0.025
= 0.0025 mol
Answer:
0.0025 mol
2026 NECO Practical Chemistry Questions and Answers
QUESTION 2 – Qualitative Analysis of Specimen C
Experiment
Add sodium hydroxide solution to specimen C.
Observation
Light blue precipitate formed.
Precipitate insoluble in excess NaOH.
Inference
Copper (II) ion present.
Cu²⁺
Additional Test
Add aqueous ammonia.
Observation
Light blue precipitate dissolves in excess ammonia to give deep blue solution.
Inference
Copper (II) ion confirmed.
Equation
Cu²⁺ + 2OH⁻ → Cu(OH)₂
QUESTION 3 – Qualitative Analysis of Specimen D
Procedure
Add sodium hydroxide solution.
Observation
Dirty green precipitate formed.
Turns brown on standing.
Inference
Iron (II) ion present.
Confirmation
Add aqueous ammonia.
Observation
Green precipitate formed.
Turns brown after exposure to air.
Inference
Fe²⁺ confirmed.
Equation
Fe²⁺ + 2OH⁻ → Fe(OH)₂
QUESTION 4 – Anion Test
Procedure
Add dilute nitric acid to specimen.
Add barium chloride solution.
Observation
White precipitate formed.
Precipitate insoluble in dilute nitric acid.
Inference
Sulphate ion present.
SO₄²⁻
Equation
Ba²⁺ + SO₄²⁻ → BaSO₄
QUESTION 5 – Gas Preparation and Identification
Procedure
Add dilute hydrochloric acid to marble chips.
Observation
Effervescence observed.
Gas evolved.
Test
Pass gas through lime water.
Observation
Lime water turns milky.
Inference
Carbon dioxide present.
Equation
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
QUESTION 6 – Determination of Water of Crystallization
A hydrated salt has:
Mass of crucible = 20.00 g
Mass of crucible + hydrated salt = 24.50 g
Mass after heating = 23.60 g
Calculate:
(a) Mass of hydrated salt
24.50 − 20.00
= 4.50 g
(b) Mass of water lost
24.50 − 23.60
= 0.90 g
(c) Percentage water
Percentage water
= (0.90 ÷ 4.50) × 100
= 20%
Answer:
20%
2026 NECO Practical Chemistry Questions and Answers
QUESTION 7 – Solubility and Crystallization
Procedure
Heat saturated solution of potassium nitrate.
Allow to cool.
Observation
Crystals formed on cooling.
Explain why crystals formed.
Answer:
The solubility of potassium nitrate decreases as temperature decreases. Excess dissolved salt separates out as crystals when the solution cools.
State two conditions necessary for crystallization.
Answer:
- Saturated solution.
- Slow cooling.
QUESTION 8 – Practical Calculations (Advanced NECO Standard)
A student dissolved 5.30 g of sodium carbonate (Na₂CO₃) in water and made up the solution to 250 cm³.
Calculate:
(a) Molar mass of Na₂CO₃
Na = 23 × 2 = 46
C = 12
O = 16 × 3 = 48
Total = 106 g mol⁻¹
Answer:
106 g mol⁻¹
(b) Number of moles present
Moles = Mass ÷ Molar Mass
= 5.30 ÷ 106
= 0.05 mol
(c) Concentration of solution
Using molarity:
Volume = 250 cm³
= 0.250 dm³
Concentration
= 0.05 ÷ 0.250
= 0.20 mol dm⁻³
Answer:
0.20 mol dm⁻³
Examiner’s Expected Practical Skills for 2026
Candidates should be able to:
- Perform accurate acid-base titrations.
- Calculate concentration from titre values.
- Identify cations and anions through qualitative analysis.
- Write ionic and molecular equations.
- Carry out gas tests correctly.
- Determine percentage composition experimentally.
- Explain crystallization and purification techniques.
- Apply mole concepts and concentration calculations accurately.
- Distinguish between observations and inferences.
- Present practical results in standard NECO examination format.
These 2026 NECO Practical Chemistry Questions and Answers reflect the depth, calculation methods, observations, laboratory procedures, inferences, and exam structure typically required to score high in the NECO Chemistry Practical Examination.
