Calculations with Solutions and Gases
Use this landing page to move quickly between the key quantitative chemistry pages for solutions and gases in OCR. Each card links to a focused page covering molar volume calculations, solution concentration calculations and titration calculations.
Choose a Calculations with Solutions and Gases Page
Calculations with solutions and gases connect the mole concept to measurable laboratory quantities. These pages build from calculating gas volumes, through using concentration in mol dm−3, to interpreting very small concentrations expressed in parts per million.
Key idea: Quantitative chemistry depends on choosing the correct relationship between amount of substance, volume, concentration and mass, then keeping units consistent throughout the calculation.
Volume
Molar Volume Calculations
Revise how the amount of gas in moles links to gas volume, including the use of molar gas volume in calculations.
Concentration
Concentrations of Solutions
Practise using concentration, volume and amount of substance in mol dm−3 calculations.
Calculations
Titration Calculations
Use concentration, volume and balanced equation ratios to calculate unknown concentrations from titration data.
How to Use These Pages
Start with molar volume calculations to link gases to amount of substance. Then move to concentrations of solutions, because many titration and practical chemistry questions require confident use of concentration and volume. Finally, use the titration calculations page to connect solution concentration with reacting mole ratios and practical volumetric analysis.
Exam focus: Always check units before substituting numbers. Volumes may need converting between cm3 and dm3, and titration calculations usually require the balanced equation ratio before finding the unknown concentration.
Copyright notice: This revision page, including its written explanations, layout and teaching sequence, is produced for Online Learning System by Dr. Mohammed Al-Fatah. It is intended for student revision and may not be copied, redistributed or republished without permission.
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