Scientific Method Tutorial

The scientific method consists of several steps: observation, purpose, hypothesis, experiment, data, conclusion. You may remember a mnemonic device from Natural Science to help you remember the order of the steps (Our pizza has extra delicious cheese!)

Observations

There are two types of observations. Scientists uses all of their senses to gather information. They might make the external image scientificmethod.jpgobservations directly or indirectly. Direct observations do not require any tools or equipment. They might include such recordings as an object's color, the texture of an organism's skin or the odor a chemical reaction produces. Indirect observations involve a scientist using some sort of apparatus to collect information such as a microscope or thermometer. During a laboratory you may need to make a combination of observations. Observations can also be described as being quantitative or qualitative. The following are two different observations of temperature:
  1. The test tube became hotter. (qualitative)
  2. The test tube temperature increased from 76˚ to 97˚F. (quantitative)

Purpose

States the problem you are investigating. "The purpose of this lab is to...."

Hypothesis

A hypothesis could be described as an educated guess (prediction). It is written in “If...then...” format. If the (independent variable) is (increased or decreased), then the (dependent variable) will (increase, decrease or remain constant).

Data

Includes all the information you collected in the experiment which may consist of:
  • charts, tables & graphs
  • formulas & calculations
  • sketches & diagrams
Typically the data section has multiple trials with calculated averages. A large sample size is preferred to a smaller one.

Experiment

This section consists of a series of numbered steps describing exactly how you performed the experiment. The instructions should allow someone to repeat your experiment and get the same results.

Conclusion

  • Restate your hypothesis
  • State whether your results support or do not support your hypothesis. Use an explanation and quantitative data from your results to support your answer.
  • Explain two possible sources of error and how you would correct them if you did the experiment again.
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Scientific Method Quiz

Test your knowledge of the tutorial above by taking the quiz below.

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