What is the pH of a 0.050 mol/L aqueous solution of barium hydroxide, Ba(OH)2, at 25 degrees Celsius?
Answer and explanation
Correct answer: B. 13.00
- Step 1: Ba(OH)2 is a strong diprotic base: Ba(OH)2 -> Ba^2+ + 2 OH^-. Step 2. [OH-] = 2 0.050 = 0.100 mol/L. pOH = -log10(0.100) = 1.00. pH = 14.00 - pOH = 13.00. Answer: 13.00. Why not the others:* Failing to double hydroxide concentration yields pOH = 1.30, giving erroneous pH 12.70.
Practise more Chemical Equilibrium, Thermodynamics, Electrochemistry and Spectroscopy.
Free questions with an explanation for every one, and full timed New Zealand Scholarship mock tests.
More Chemical Equilibrium, Thermodynamics, Electrochemistry and Spectroscopy questions
- In 1H NMR spectroscopy, what splitting pattern is observed for the hydrogen atoms on the -CH2- carbon of pure bromoethane (CH3-CH2-Br)?
- According to Le Chatelier's principle, how does increasing total pressure at constant temperature affect the Haber equilibrium: N2(g) + 3 H2…
- For an electrochemical cell with standard potential E_cell^0 = +1.10 V at 298 K, what is the sign and meaning of standard Gibbs free energy…
- What is the solubility product expression K_sp for sparingly soluble silver phosphate, Ag3PO4?
- What prominent absorption band in an infrared (IR) spectrum confirms the presence of a carboxylic acid -O-H group?
- Under what conditions is a chemical reaction always thermodynamically spontaneous at all temperatures?