大象传媒

  • Chemical analysis

    • Separating chemical mixtures

      There are different ways to separate mixtures, for example by filtration, crystallisation, distillation or chromatography. The method chosen depends upon the type of mixture.

    • Finding the composition of unknown samples

      Quantitative analysis is used by chemists to make measurements and calculations. Alkalis neutralise acids to make salts and water. Their concentration can be analysed using titrations.

    • Calculating amounts of substances

      No atoms are created or destroyed during a chemical reaction. This allows calculations to be made on the quantities of substances that react and of the products made.

    • Calculating yields - OCR 21st Century

      The percentage yield shows how much product is obtained compared to the maximum possible mass. Molar gas volume can be used to make calculations about reactions between gases.

    • Measuring the amounts of chemicals in solutions

      Quantitative analysis is used by chemists to make measurements and calculations. Alkalis neutralise acids to make salts and water. Their concentration can be analysed using titrations.

    • Sample exam questions - chemical analysis

      Understanding how to approach exam questions helps to boost exam performance. Question types will include multiple choice, structured, mathematical and practical questions.

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