CKal <Ka<Ka3 The predominant spiP Theidmostlydue tothe hydrolysis of None of the above 8.If NaNOz)is added to an aqueous solution of the weak acid HNO2: The pH rises CThe pH falls The pH is unaffected 9.Assume you have a basic buffer system composed of ammonia and ammonium chloride. The Henderson-Hasselbach equation is pH=pKa-log lacid /base).Here,the acid and base are: CHao'and OH C H:O'and H2O C NHs and NH" C NH'and NH3 C NH'andOH 10.CaF2 is a sparingly soluble salt.HF is a weak acid.If the pH of a solution of CaFzis lowered,the solubility of CaF2 will: CIncrease CDecrease
Ka1 < Ka2 < Ka3 The predominant species in solution is PO4 -3 The predominant species in solution is HPO4 -2 The solution is acidic mostly due to the hydrolysis of H2PO4 - None of the above 8. If NaNO2(s) is added to an aqueous solution of the weak acid HNO2: The pH rises The pH falls The pH is unaffected 9. Assume you have a basic buffer system composed of ammonia and ammonium chloride. The Henderson-Hasselbach equation is pH = pKa - log{[acid]/[base]}. Here, the acid and base are: H3O+ and OHH3O+ and H2O NH3 and NH4 + NH4 + and NH3 NH4 + and OH- 10. CaF2 is a sparingly soluble salt. HF is a weak acid. If the pH of a solution of CaF2 is lowered, the solubility of CaF2 will: Increase Decrease 6
CNot change Answer: Question1. All of these are true Question 2. A proton is transferred from the acid to the base in an acid-base reaction.Water is not necessarily involved. Question 3. The extraatom in HCIO2 creates more electronegativity at that end of the molecule pulling electron density away from the O-H bond and thus weakening it. Question 4. Cl is more electronegative.This makes the H-CI bond more ionic,thus stronger.Thus. HCI is a weaker acid. Question 5. All of these are true!Strong acids have weak conjugate bases. Question 6. All of these are true!Weak bases have strong conjugate acids. Question 7. None of these are true!Kal>Ka2Ka3,as for any polyprotic acid.Most of the acidity comes from the first dissociation
Not change Answer: Question 1. All of these are true! Question 2. A proton is transferred from the acid to the base in an acid-base reaction. Water is not necessarily involved. Question 3. The extra O atom in HClO2 creates more electronegativity at that end of the molecule, pulling electron density away from the O-H bond and thus weakening it. Question 4. Cl is more electronegative. This makes the H-Cl bond more ionic, thus stronger. Thus, HCl is a weaker acid. Question 5. All of these are true! Strong acids have weak conjugate bases. Question 6. All of these are true! Weak bases have strong conjugate acids. Question 7. None of these are true! Ka1>Ka2>Ka3, as for any polyprotic acid. Most of the acidity comes from the first dissociation. 7