IB Chemistry SL – R3.1 Reactivity: Proton Transfer Reactions

Which statement best describes a Brønsted–Lowry acid?

• A. A proton donor

• B. A proton acceptor

• C. An electron donor

• D. An electron acceptor

What is the conjugate base of H₂O?

• H₃O⁺

• OH⁻

• O²⁻

• H₂

Which pair forms a conjugate acid–base pair?

• NH₄⁺ / NH₃

• H₂ / O₂

• HCl / NaCl

• CH₄ / CH₃OH

Which of the following substances can act as both an acid and a base?

What species acts as the acid in the reaction: NH₃ + H₂O ⇌ NH₄⁺ + OH⁻ ?

• NH₃

• H₂O

• NH₄⁺

• OH⁻

Which of the following is not an amphoteric substance?

• H₂O

• HCO₃⁻

• Al₂O₃

• NaOH

In the equation HCN + OH⁻ ⇌ CN⁻ + H₂O, what acts as the base?

• HCN

• OH⁻

• CN⁻

• H₂O

The conjugate acid of NH₂⁻ is:

• NH₃

• NH₂OH

• NH₄⁺

• N₂H₄

Which of the following is a conjugate base?

• NH₃

• NH₄⁺

• NH₂OH

• N₂H₄

In pure water, the concentrations of H⁺ and OH⁻ are equal because:

• A. Water is amphoteric

• B. Water contains equal numbers of H and O atoms

• C. Water molecules self-ionize

• D. pH is always 7