Which combination of substances forms an effective buffer solution resistant to pH changes upon addition of small amounts of strong acid or base?
Answer and explanation
Correct answer: B. Acetic acid and sodium acetate
A buffer requires a weak acid and its conjugate base (or a weak base and its conjugate acid). CH3COOH is a weak acid and CH3COO- is its conjugate base. Strong acids (HCl, HNO3, H2SO4) and their salts cannot buffer around neutral pH.
Practise more Chemical Thermodynamics, Kinetics, and Equilibrium.
Free questions with an explanation for every one, and full timed Medical University Entrance Examination (Bulgaria) mock tests.
More Chemical Thermodynamics, Kinetics, and Equilibrium questions
- What thermodynamic criterion determines whether a chemical process is spontaneous at constant temperature and pressure?
- Under which thermodynamic conditions is a chemical reaction spontaneous at all temperatures?
- How does adding a chemical catalyst accelerate the rate of a chemical reaction?
- What are the units of the rate constant (k) for a second-order chemical reaction?
- If doubling the concentration of reactant A quadruples the initial rate of reaction, what is the reaction order with respect to A?
- According to the Arrhenius equation (k = A * e^(-Ea / RT)), what graph yields a straight line whose slope equals -Ea / R?