#chemistry#ae#sis

  • Hypothesis: link between independent and dependent variable, and a prediction on what is going to happen (observation).
  • Independent variable: the variable that is changed, it is the one being investigated. (Use units when possible)
  • Dependent variable: the variable that is measured (Use units when possible)
  • Control variables: Factors that are kept the same to make it a fair test
    • Preliminary work: used to identify what factors can be controlled, how to set experiment up, how to minimise uncontrollable variables.
      • Determines the accuracy of the experiment.
  • Validity vs Reliability
    • Validity: how well does it answer the question posed? is the experiment ‘fair’: all variables are the same except the one we are testing.
      • the validity of the experiment is determined by systematic error.
    • reliability: how consistent is the data
  • repetition: increases consistency thus increases reliability.
  • replication: others, using the same experiment, doing the same investigation.
  • precision: the degree of detail the equipment allows.
  • risk assessment: to reduce chances of inquiry, consider:
    • anonymity
    • confidentiality
    • voluntary participation
      • can withdraw at any time
    • informed consent