Moles, masses, concentrations, gas volumes 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 section 2.1.3 - Amount of Substance (together with the free resource - topic 10 Percentage yield and atom economy)

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.

This bundle is the second in a series covering the OCR AS Chemistry specification and relates to the following sections:
Module 2 – Foundations in chemistry
Part 1 – Atoms and reactions
2.1.3 – Amount of substance

Content covered
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)

Links
Previous bundle:
Atomic structure, masses, formulae and equations https://www.tes.com/teaching-resource/atomic-masses-formulae-and-equations-ocr-as-chemistry-12348685
Next bundle
Acids, titrations and redox
https://www.tes.com/teaching-resource/acids-titrations-and-redox-ocr-as-chemistry-12749654
Free resource - standard form, decimal places and significant figures
https://www.tes.com/teaching-resource/standard-form-decimal-places-and-significant-figures-a-level-chemistry-12405507