CHEM 1011 - WEEK 7 Questions With Complete Solutions

Aqueous salt solutions will be acidic when correct answer: The salt's cation is a strong enough acid to donate a proton to water A solution of sodium cyanide, NaCN, in water will be correct answer: Basic A buffer correct answer: Can be designed to work well at pH below 7 or above 7, but not across the entire pH range A good buffer correct answer: Should have about equal concentrations of an acid and its conjugate base The titration curve above represents the titration of correct answer: A strong acid with a strong base Acid-base indicators correct answer: Can be used to determine the pH of a solution by observing changes in color Which of the following is true of o-cresolphthalein, a pH indicator that changes from colorless to red in the color change interval of pH 8-10? correct answer: The color change would appear to be very abrupt for a titration with an endpoint at pH 9 What will be the pH of a buffer solution prepared from 0.20 mol acetic acid (CH3Cooh), 0.45 mol sodium acetate (CH3COONa), and just enough water to give 1.00 L of solution? The Ka for acetic acid id 1.75 x 10^-5. correct answer: 5.1 In the titration of 15.00 mL of 0.025 M HCL with 0.025 M NaOH, what is the pH after 12.50 mL of NaOH is added? correct answer: 2.6 In the titration of 15.00 mL of 0.050 M CH3COOH