The question
Name: ______________________ Date: ____________ A strong acid and a weak acid at the same concentration (4 points)
Experimental setup
Two acid solutions
Flask 1 contains 50.0 mL of 0.050 M HNO₃. Flask 2 contains 50.0 mL of 0.050 M HNO₂ (Ka = 4.0 × 10⁻⁴). Both are at 25 °C.
(a) Calculate the pH of the solution in each flask. [2 points]
(b) A student says Flask 2 will need less NaOH to reach the equivalence point, because it has fewer H₃O⁺ ions. Do you agree or disagree? Justify your answer. [1 point]
(c) Each flask is diluted tenfold with water. Explain why the pH of Flask 2 rises by less than the pH of Flask 1. [1 point]