SCH4U BUNDLED TESTS ACTUAL EXAMS
2026 COMPLETE QUESTIONS AND
SOLUTIONS GRADED A+
⩥ What is the oxidation number for elements in their elemental state?
Answer: 0
⩥ What is the oxidation number for a monoatomic ion? Answer: It is
equal to its charge.
⩥ What is the oxidation number for Group 1 elements? Answer: +1
⩥ What is the oxidation number for Group 2 elements? Answer: +2
⩥ What is the usual oxidation number of oxygen? Answer: -2
⩥ What is the oxidation number of oxygen in peroxides? Answer: -1
⩥ What is the usual oxidation number of hydrogen? Answer: +1
⩥ What is the oxidation number of hydrogen in metal hydrides? Answer:
-1
,⩥ What is the oxidation number of fluorine? Answer: -1
⩥ What must the sum of oxidation numbers equal? Answer: The net
charge of the molecule or ion.
⩥ What does LEO GER stand for? Answer: Loss of Electrons =
Oxidation, Gain of Electrons = Reduction.
⩥ What occurs at the anode in a redox reaction? Answer: Oxidation.
⩥ What occurs at the cathode in a redox reaction? Answer: Reduction.
⩥ What is a voltaic (galvanic) cell? Answer: A device that uses
spontaneous redox reactions to generate electricity.
⩥ What is the purpose of a salt bridge in a voltaic cell? Answer: To
allow ion flow and maintain electrical neutrality.
⩥ What does a positive E°cell indicate? Answer: A spontaneous
reaction.
, ⩥ What is the Standard Hydrogen Electrode (SHE)? Answer: A
reference electrode with a potential of 0.00 V.
⩥ What is corrosion? Answer: Unwanted oxidation of a metal.
⩥ What is the overall reaction for rusting of iron? Answer: Fe²⁺ + 2OH⁻
→ Fe(OH)₂ → Fe₂O₃ (rust).
⩥ What are two methods to prevent corrosion? Answer: Coating and
galvanizing.
⩥ What effect does temperature have on reaction rates? Answer: Higher
temperature increases reaction rates.
⩥ How does concentration affect reaction rates? Answer: Higher
concentration increases reaction rates.
⩥ What role does a catalyst play in a reaction? Answer: It increases the
reaction rate.
⩥ What is the significance of balancing redox equations? Answer: To
ensure mass and charge conservation.
2026 COMPLETE QUESTIONS AND
SOLUTIONS GRADED A+
⩥ What is the oxidation number for elements in their elemental state?
Answer: 0
⩥ What is the oxidation number for a monoatomic ion? Answer: It is
equal to its charge.
⩥ What is the oxidation number for Group 1 elements? Answer: +1
⩥ What is the oxidation number for Group 2 elements? Answer: +2
⩥ What is the usual oxidation number of oxygen? Answer: -2
⩥ What is the oxidation number of oxygen in peroxides? Answer: -1
⩥ What is the usual oxidation number of hydrogen? Answer: +1
⩥ What is the oxidation number of hydrogen in metal hydrides? Answer:
-1
,⩥ What is the oxidation number of fluorine? Answer: -1
⩥ What must the sum of oxidation numbers equal? Answer: The net
charge of the molecule or ion.
⩥ What does LEO GER stand for? Answer: Loss of Electrons =
Oxidation, Gain of Electrons = Reduction.
⩥ What occurs at the anode in a redox reaction? Answer: Oxidation.
⩥ What occurs at the cathode in a redox reaction? Answer: Reduction.
⩥ What is a voltaic (galvanic) cell? Answer: A device that uses
spontaneous redox reactions to generate electricity.
⩥ What is the purpose of a salt bridge in a voltaic cell? Answer: To
allow ion flow and maintain electrical neutrality.
⩥ What does a positive E°cell indicate? Answer: A spontaneous
reaction.
, ⩥ What is the Standard Hydrogen Electrode (SHE)? Answer: A
reference electrode with a potential of 0.00 V.
⩥ What is corrosion? Answer: Unwanted oxidation of a metal.
⩥ What is the overall reaction for rusting of iron? Answer: Fe²⁺ + 2OH⁻
→ Fe(OH)₂ → Fe₂O₃ (rust).
⩥ What are two methods to prevent corrosion? Answer: Coating and
galvanizing.
⩥ What effect does temperature have on reaction rates? Answer: Higher
temperature increases reaction rates.
⩥ How does concentration affect reaction rates? Answer: Higher
concentration increases reaction rates.
⩥ What role does a catalyst play in a reaction? Answer: It increases the
reaction rate.
⩥ What is the significance of balancing redox equations? Answer: To
ensure mass and charge conservation.
