Lecture 01, 2, 3

• What is the pH scale used for?

  Measuring acidity and basicity of solutions

  
• What defines a strong acid?

  It completely dissociates into ions in solution
• What is the Brönsted-Lowry definition of an acid?

  An acid is a proton donor
• What is the Brönsted-Lowry definition of a base?

  A base is a proton acceptor
• What is the equilibrium expression for a weak acid HA?

  HA ⇌ H+ + A-
• How does the strength of an acid relate to its ionisation?

  Stronger acids ionise more completely in solution
• What is the acidity constant (Ka)?

  It measures the strength of a weak acid

  
• What is a polyprotic acid?

  An acid that can donate multiple protons
• What does pKb represent?

  It measures the strength of a weak base
• What is the relationship between pKa and acid strength?

  Lower pKa indicates a stronger acid

  
• What is the self-ionisation of water?

  Water dissociates into H+ and OH- ions
• What is the ionisation product of water (Kw) at 25°C?

  1 x 10^-14 mol²L^-2

  
• What does the Henderson-Hasselbalch equation calculate?

  The pH of a buffer solution

  
• What is buffer capacity?

  The amount of acid/base to change pH by one unit
• What happens at the equivalence point in a titration?

  All acid has reacted with the base

  
• What is the pH at the equivalence point for strong acid-strong base titration?

  pH is 7
• What is the pH at the equivalence point for weak acid-strong base titration?

  pH is greater than 7
• What is the pH at the equivalence point for strong acid-weak base titration?

  pH is less than 7
• What is the significance of the pKa value in drug formulation?

  It helps maintain drug solubility and stability
• How does the pH affect drug absorption?

  It influences drug solubility and ionisation
• What is the role of buffers in biological systems?

  They maintain stable pH in biological fluids
• What is the relationship between Ka and Kb for a conjugate acid-base pair?

  KaKb = Kw
• What does a change of 1 pH unit represent?

  A 10-fold change in [H+]
• How do you calculate the pH of a strong acid solution?

  pH = -log [H+]
• How do you calculate the pH of a strong base solution?

  pH = 14 - pOH
• How do you calculate the pH of a weak acid solution?

  Use the formula: pH = -log [H3O+]
• How do you determine the concentration of an unknown acid using titration?

  Use the equivalence point volume and concentration
• What factors affect the choice of buffer solution?

  pH range and compatibility with biological systems
• What is the significance of the Henderson-Hasselbalch equation in buffer systems?

  It relates pH to the ratio of acid and conjugate base

  
• What is the effect of adding a small amount of acid to a buffer solution?

  The pH changes minimally
• What is the role of the acetate ion in the buffer system?

  It acts as the conjugate base of acetic acid
• What happens to the pH of a solution when a strong acid is added to a weak base?

  The pH decreases below 7
• What is the effect of temperature on the ionisation of water?

  Higher temperatures increase ionisation
• What is the significance of the pKa value in drug formulation?

  It helps maintain drug solubility and stability
• What is the relationship between pKa and drug absorption?

  pKa influences drug solubility and ionisation
• What is the effect of adding a strong base to a weak acid?

  The pH increases above 7
• What is the effect of adding a weak acid to a strong base?

  The pH increases but remains below 14
• What is the significance of the equivalence point in titration?

  It indicates complete reaction of acid and base
• What is the role of the conjugate base in acid-base reactions?

  It can accept protons to form the acid
• What is the effect of temperature on the pH of a solution?

  Temperature changes can affect pH readings