pH of Weak Acids (OCR)

Acids, Bases & Buffers (OCR)

10 Full Lesson Bundle + BONUS lesson on Acids, bases & buffers. This bundle covers the OCR A Level Chemistry specification. Please review the learning objectives below. **Lesson 1: Bronsted-Lowry Acid and Bases** 1. To describe the difference between a BrØnsted Lowry acid and base 2. To identify conjugate acid-base pairs 3. To explain the difference between monobasic, dibasic and tribasic acids 4. To understand the role of H+ in the reactions of acids with metals and bases (including carbonates, metal oxides and alkalis), using ionic equations **Lesson 2: Strong Acids & The pH Scale** 1. To calculate the pH of a strong acid 2. To convert between pH and [H+(aq)] 3. To apply the relationship between pH and [H+(aq)] to work out pH changes after dilution **Lesson 3 - The Acid Dissociation Constant ** 1. To understand the acid dissociation constant, Ka, as the extent of acid dissociation 2. To know the relationship between Ka and pKa 3. To convert between Ka and pKa **Lesson 4- pH of weak acids** 1. To recall the expression of pH for weak monobasic acids 2. To calculate the pH of weak monobasic acids using approximations 3. To analyse the limitations of using approximations to Ka related calculations for ‘stronger’ weak acids **Lesson 5 - The ionic product of water** 1. To recall the expression for the ionic product of water, Kw (ionisation of water) 2. To calculate the pH of strong bases using Kw 3. To apply the principles for Kc, Kp to Kw **Lesson 6-9 - Buffer Solutions (3 part lesson)** **Part 1: Explaining How Buffer Solutions Work** 1. To know a buffer solution is a system that minimises pH changes on addition of small amounts of an acid or base 2. To describe how a buffer solution is formed using weak acids, salts and strong alkalis 3. To explain the role of the conjugate acid-base pair in an acid buffer solution such as how the blood pH is controlled by the carbonic acid–hydrogencarbonate buffer system **Part 2: Buffer Solution Calculations (Part 1)** 1. To calculate the pH of a buffer solution containing a weak acid and the salt of a weak acid by using the Ka expression and pH equation 2. To calculate equilibrium concentrations, moles or mass of the components of a weak acid-salt of a weak acid buffer solution **Part 3: Buffer Solution Calculations (Part 2)** 1. To calculate the pH of a weak acid-strong alkali buffer solution 2. To calculate equilibrium concentrations, moles or mass of the components of a weak acid- strong alkali buffer solution **BONUS Lesson 9 : Revision on Buffer Solutions** 1. To review how to calculate the pH of a buffer solution containing a weak acid and a strong alkali 2. To review how to calculate the pH of a buffer solution containing a weak acid and the salt of the weak acid **Lesson 10- Neutralisation & Titration Curves** 1. To interpret titration curves of strong and weak acids and strong and weak bases 2. To construct titration curve diagrams of strong and weak acids and strong and weak bases **Lesson 11- pH indicators & Titration Curves ** 1. To explain indicator colour changes in terms of equilibrium shift between the HA and A- forms of the indicator 2. To explain the choice of suitable indicators given the pH range of the indicator 3. To describe an experiment for creating a titration curve ***Declaimer: Please refrain from purchasing this popular resource for an interview lesson or a formal observation. This is because planning your own lessons including using your own lesson PowerPoints is a fundamental skill of a qualified/unqualified teacher that will be reviewed during these scenarios outlined above***