CHEMISTRY FORM SIX – JOINT MOCK SERIES EXAM 2026 MCN SUPER SERIES
2.(a) State the following:
(i) Pauli’s exclusion principal
(ii) Aufbau building principal
(iii) Hund’s rule of maximum multiplicity
(iv) Half-filled and full-filled orbital rule (02 Marks)
(b) (i) Predict the geometry of water, basing on the valence shell Electron pair Repulsion (VSEPR) theory.
(ii) Explain why water (H2O) is a polar molecule while carbon dioxide is non polar.
(iii) Give two (02) reasons why oxygen molecule (O2) is more stable than two separate oxygen atoms.(04=12 Marks)
(c) Give two (02) reasons for the observed difference in bond strength between sigma and pi bonds in compounds. (01 Marks)
(d) Briefly explain why the following quantum number are not allowed.
(i) n = 1, l = 1, m = 0
(ii) n = 1, l = 0, m = 2
(iii) n = 4, l = 3, m = 4
(iv) n = 0, l = −1, m = 1
(v) n = 2, l = −1, m = 0 (02 =12Marks)
3.(a) (i) State three (03) gas laws that make ideal gas equation, then deduce ideal gas equation.
(ii) Under what conditions do real gases fail to obey Charles ’law and Boyle’s laws? (02 Marks)
(b) A mixture of 0.5 mole of CO and 0.5 mole of CO2 is taken in a vessel and allowed to effuse out through a pinhole into another vessel which has vacuum. If a total of A mole has effused out in time t, show that M1A + M2(1 − A) = 36, where M1 and M2 are mean molar masses of the mixture that has effused out and the mixture still remaining in vessel respectively.)
