Chemistry Quiz

What is oxidation?

• Gain of electrons

• Loss of electrons

• Gain of protons

• Loss of neutrons

What is reduction?

• Loss of electrons

• Gain of electrons

• Gain of oxygen

• Loss of hydrogen

Which of the following is the reducing agent?

• The substance that gains electrons

• The substance that loses electrons

• The substance that forms a precipitate

• The substance that changes color

In the reaction: Zn + Cu²⁺ → Zn²⁺ + Cu, which species is oxidized?

• Zn

• Cu²⁺

• Zn²⁺

• Cu

What is the oxidation state of hydrogen in water (H₂O)?

• +1

• -1

• 0

• +2

What is the oxidation state of oxygen in most compounds?

• +2

• -1

• -2

• 0

In H₂O₂ (hydrogen peroxide), the oxidation state of oxygen is:

• -2

• -1

• 0

• +1

Which species is being reduced in this reaction: Cl₂ + 2e⁻ → 2Cl⁻?

• Cl⁻

• Cl₂

• e⁻

• None

A redox reaction always involves:

• Precipitation

• Change in temperature

• Transfer of electrons

• Formation of gas

Which of the following is a redox reaction?

• HCl + NaOH → NaCl + H₂O

• AgNO₃ + NaCl → AgCl + NaNO₃

• Zn + HCl → ZnCl₂ + H₂

• Na₂SO₄ + BaCl₂ → BaSO₄ + 2NaCl