Atoms and Reactions OCR AS Chemistry

This bundle is ideal for classroom or home learning and covers the whole of the OCR A level chemistry specification sections 2.1 - Atoms and Reactions
Each topic includes a fully interactive PowerPoint including starter, group activities, questions and plenary along with a worksheet and a lesson plan. Answers to all exercises are provided. Some of the resources include a PowerPoint quiz. A practical activity on titration is also included.

This bundle relates to the following sections of the OCR AS Chemistry specification:
Module 2 – Foundations in chemistry
Part 1 – Atoms and reactions (whole)
2.1.1 – Atomic structure and isotopes
2.1.2 – Compounds, formulae and equations
2.1.3 – Amount of substance
2.1.4 – Acids
2.1.5 − Redox

Content covered:

The changing atom
How Science Works - HSW7 - The changing accepted models of atomic structure over time.
The contributions of five scientists to the development of the theory of atomic structure.

Atomic structure
• Protons, neutrons and electrons – mass and relative charge
• Atomic number and mass number
• Isotopes
• Key definitions

Atomic masses
• Relative masses - comparison of masses to carbon-12
• Calculating relative atomic mass from the masses and abundances of the isotopes
• Mass spectrometry and its use in the above
• Calculating relative molecular and relative formula masses from formulae
• Key definitions of relative atomic mass and relative isotopic mass

Formulae and equations
• Formulae of ions
• Predicting ionic charges from the Periodic Table
• Writing the formulae of ionic compounds and elements
• Writing and balancing equations
• Common types of reaction and their equations

Amount of substance and the mole
• Relative masses and the mole
• Avogadro constant
• Calculating number of atoms
• Amount of substance
• Molar mass
• Calculating amount of substance from total mass and vice versa
• Mole triangle

Determining formulae
• Definitions and use of the terms empirical and molecular formula
• Simplest whole number ratios
• Calculations of empirical and molecular formulae, from composition by mass or percentage compositions by mass and relative molecular mass
• Calculating % by mass from the formula
• The terms anhydrous, hydrated and water of crystallisation
• Calculation of the formula of a hydrated salt from given percentage composition, mass composition or based on experimental results

Moles and gas volumes
• Molar volume of a gas
• Moles and gas volume triangle
• Summary of relationships for gases between amount of substance, volume, mass and number of molecules
• Calculating amount of substance from volume of gas and vice versa
• Ideal gases
• The ideal gas equation

Moles and concentrations of solutions
• Definitions and use of the terms concentration and mass concentration
• Concentrated and dilute
• Relationship between concentration, amount in mol and volume including concentration triangle
• Calculating concentration, amount in mol, volume and mass from given data
• Example calculations
• Mass concentrations
• Choosing the correct glassware to measure volumes
• Standard solutions
• Practical activity – making up a standard solution
• Diluting solutions and calculations
• Practical activity – diluting solutions

Moles and reactions
• Balanced chemical equations and stoichiometry
• Molar ratios
• Using molar ratio to calculate amounts in moles of reactants and products in a chemical reaction
• Using molar ratio to calculate masses of reactants and products in a chemical reaction
• Using molar ratio to calculate volumes of gases in a chemical reaction
• Flow diagrams showing steps in calculations involving quantities of reacting substances
• Example calculations – clearly illustrated in a highly visual way

Percentage yield and atom economy
• Introduction to Green Chemistry
• Reasons why reactions do not have 100% yield
• % yield and how to calculate it
• Calculations of % yield involving limiting reactant
• Atom economy and its importance in the sustainability of a chemical process
• Calculating atom economy
• Example calculations – clearly illustrated in a highly visual way
• Differences between atom economy and % yield
• Comparing chemical processes in terms of sustainability (using production of ethanol as an example)

Acids and bases
• Definitions of acid, base, alkali and salt
• Formulae of acids, bases, alkalis and salts
• The relationship between bases and alkalis
• The pH scale
• Everyday examples of acids and bases
• Weak and strong acids
• Diprotic acids
• Writing and balancing neutralization reactions (including acid-carbonate reactions)
• Ionic equations

Acid-base titrations
• Titration and uses
• Standard solution
• Glassware and procedure for titration with detailed hints for technique
• Reading burette
• Recording titration results and calculating the mean
• Titration calculations
• Examples of structured and unstructured calculations
• Revision of calculations involving masses and volumes
• Practical titration activity
• Evaluation of titration experiment
• Uncertainties and calculating % uncertainties
• Procedural errors

Redox
• Redox definition in terms of electron transfer
• Oxidation numbers and how to calculate them
• Oxidation number in chemical names
• Redox definition in terms of oxidation number
• Using oxidation numbers to identify redox reactions and determine what has been oxidised and reduced
• Oxidising and reducing agents
• Disproportionation as oxidation and reduction of the same element

Links
Next bundle:
Electrons and bonding
https://www.tes.com/teaching-resource/electrons-and-bonding-ocr-as-chemistry-12605443
Next topic
Topic 14 – Electron configuration – shells, sub-shells and orbitals
https://www.tes.com/teaching-resource/electron-configuration-shells-sub-shells-and-orbitals-ocr-as-chemistry-12207312