✨Module 1: Practical skills Flashcards
(14 cards)
What is a negative control?
A sample that does not receive any type of treatment and so shouldn’t show any change in an experiment.
What does a repeatable experiment mean?
If you repeat the experiment with the same method and equipment, you should get the same results.
What are valid results?
Results that correspond to the real properties.
3 things to consider when carrying out a risk assessment?
Dangers of the experiment.
Who is at risk.
How the risk can be reduced.
What is a graduated pipette?
Pipette with a scale to measure specific volumes. Make sure to read from the bottom of the meniscus at eye level.
How to accurately use a water bath.
Allow time for the water baths to heat up before starting the experiment. Solutions will also need to acclimatise to the temperature before starting.
What are precise results?
How similar repeat reading are to each other. Don’t vary much from the mean. Results very close together. Measurements to a greater number of decimal places are said to be more precise than those to a whole number.
What is meant by accuracy?
How close a measurement is to the true value. We need to reduce errors. Faulty instruments can produce systematic errors that are repeated consistently every time the instrument is used.
Reliability?
Experiments are repeated many times to ensure the reliability of results.
Validity.
The other variables in the experiment are identified and controlled in order to ensure the validity of an experiment.
Reproducibility?
Someone does the same method and produce similar results.
Repeatability?
Same experiment has been conducted again, producing similar results. This demonstrates reliability and validity, showing that results are consistent and not due to random chance.
Accuracy.
How closely the results are to the true value. It’s crucial to minimise errors and reliable results. To improve accuracy, use calibrated measurements, repeat multiple times to reduce random errors and identify outliers.
Good accuracy determines reliability and validity.
Precision.
How close repeated measurements are to each other.
