PassSpark

NECO SSCE Chemistry 2023 past questions and answers

This 2023 NECO SSCE Chemistry set has 40 practice questions. Try these 5 free sample questions, tap a question to reveal the answer and explanation. Then practise the whole 2023 set with instant marking.

Practise the full 2023 setTimed exam mode

Sample NECO SSCE Chemistry 2023 questions

1. For the equilibrium N2(g) + 3H2(g) ⇌ 2NH3(g) at constant temperature, which change increases the equilibrium yield of ammonia?
  1. Adding a catalyst
  2. Increasing the pressure
  3. Decreasing the pressure
  4. Adding ammonia

Answer: B. Increasing the pressure

Higher pressure favours the side with fewer gas molecules, which is the ammonia side.

2. What mass of copper is deposited when 2 faradays of charge pass through molten copper(II) chloride? (Cu = 63.5 g mol-1; Cu2+ + 2e- -> Cu)
  1. 31.75 g
  2. 127.0 g
  3. 6.35 g
  4. 63.5 g

Answer: D. 63.5 g

Two faradays provide the two moles of electrons needed to deposit one mole, or 63.5 g, of copper.

3. How does a catalyst generally increase the rate of a chemical reaction?
  1. It provides an alternative pathway with lower activation energy
  2. It increases the enthalpy change of the reaction
  3. It increases the equilibrium constant
  4. It is permanently consumed as a reactant

Answer: A. It provides an alternative pathway with lower activation energy

A catalyst increases reaction rate by providing a pathway with lower activation energy.

4. A reaction releases heat to its surroundings at constant pressure; what is the sign of its enthalpy change, ΔH?
  1. Positive
  2. Zero
  3. Negative
  4. It must equal the activation energy

Answer: C. Negative

A reaction that releases heat is exothermic and has a negative enthalpy change.

5. What volume is occupied by 0.50 mol of an ideal gas at 273 K and 1 atmosphere, where the molar gas volume is 22.4 dm3 mol-1?
  1. 5.60 dm3
  2. 11.2 dm3
  3. 22.4 dm3
  4. 44.8 dm3

Answer: B. 11.2 dm3

The volume is 0.50 mol multiplied by 22.4 dm3 mol-1, which equals 11.2 dm3.

More NECO SSCE Chemistry years

20262025202420222021202020192018201720162015201420132012201120102009200820072006200520042003200220012000

All NECO SSCE Chemistry years · NECO SSCE subjects

PassSpark questions are original practice questions written to each exam's syllabus and format, in the style of past questions. They are not official past papers and are not affiliated with JAMB, WAEC, NECO, any university or any exam body.