Unit 1 - Introduction to Science

Observation: Receiving knowledge of the outside world through our senses, or recording information using senses, or recording information using scientific tools and instruments.  

Quantitative Observations: The depiction of obtained variables in terms of their quantity. Use tools to find this information. The primary focus is on numbers and values. These results are measurable.  

Qualitative Observations: A subjective method of gathering information by using the researcher’s sensory organs – sight, smell, touch, taste, and hearing. These have no numbers – they describe using words.  

Inference: A conclusion that you reach after an observation. It is what you think or decide about something that you have observed.  

Bunsen Burner 

A Bunsen burner is a device used in a chemistry lab for heating substances. 

Air Hole Position 

Type of Flame 

Use 

Colour of Flame 

Open 

Roaring flame 

Heating things up quickly 

 

Half Open 

Blue flame 

Heating things up gently 

 

Closed 

Yellow safety flame 

When the Bunsen Burner is being lit or is not being used for heating 

 

 

Meniscus 

When measuring liquids like water, you will encounter a phenomenon where water clings to the edge of the container and "climbs" up. This curved surface is called the meniscus. 

  • Always read at eye level on a flat surface. 

  • Read from the center of the meniscus 

 

Laboratory Equipment 

Equipment 

Use 

Beaker 

Container for mixing or heating liquids and other substances 

Bosshead 

Holds the clamp to a retort stand 

Bunsen Burner 

Heats substances 

Clamp 

Holds objects at the required height on a retort stand 

Conical flask 

Container for mixing substances or collecting filtered substances 

Evaporating dish 

Container for heating small amounts of substances over a Bunsen Burner 

Filter funnel 

Used with filter paper to filter substances 

Gauze mat 

Supports a container over a Bunsen Burner while it is heated 

Heatproof mat 

Protects benches from damage 

Measuring cylinder 

Used to measure the volume of a liquid accurately 

Retort stand 

Used with a clamp and bosshead to hold equipment at the required height 

Safety glasses 

Protect eyes 

Spatula 

Used to pick up small amounts of solid substances 

Stirring rod 

Used to stir mixtures 

Test tube 

Container for holding, heating or mixing small amounts of substances 

Test-tube holder 

Holds a test tube while it is being heated 

Test-tube rack 

Holds test tubes upright 

Thermometer 

Measures temperature 

Tongs 

Used to hold small objects while they are heated or to pick up hot glassware 

Tripod 

Supports a gauze mat over a Bunsen burner 

Watchglass 

Holds small quantities of solids 

 

Variable: A condition in an experiment that can change.  

Independent variable: The variable that the scientist changes to observe its effect on another variable.  

Dependent variable: The variable that is expected to change when the independent variable is changed. The dependent variable is observed or measured during the experiment.  

Control: A parallel experiment where everything is the same as the test set-up except the variable. It is used to ensure that the result is due to the variable and nothing else.  

Trials: Repeated tests of the same experiment.  

Fair test: A method for determining an answer to a problem without favoring any particular outcome. Another name is ‘controlled experiment’. 

There is only one variable that is changed because it allows the person conducting the test to know that no other variable has affected the results of the test.  

 

Scientific Method: 

The technique used in the construction and testing of a scientific hypothesis. It is the process of observing, asking questions, and seeking answers through tests and experiments.  

  1. Make an observation 

  1. Ask a question 

  1. Develop a hypothesis or prediction 

  1. Test the prediction 

  1. Analyse results 

  1. Record the results against hypothesis 

  1. Make a conclusion 

 

Scientific Report: 

Introduction - Why did you do your experiment? 

Aim: A single statement that describes the purpose or reason why we are conducting an experiment. It should be brief and concise. It should state the purpose of the experiment without providing a prediction.  

“To determine the effect of [independent variable] on [dependent variable]. This will be done by...” 

Hypothesis: An ‘educated guess’ based on prior knowledge and observation. A hypothesis also includes an explanation of why the guess may be correct.  

“If [independent variable] [increases/decreases], then [dependent variable] [increases/decreases] because [scientific reasoning].” 

Methodology – What experiment did you do and how did you do it? 

Materials:  

Results – What happened when you did it? 

Discussion- What do the results mean? 

Conclusion: 

  • Restate the purpose of the experiment (include IV and DV variables) 

  • State the major findings (Summarize data and graph results) 

  • Was the hypothesis supported by the data? 

  • What were your errors? 

  • How could this experiment be improved? 

  • What could be studied next after this experiment? What new experiment could continue study of this topic? 

 

Prediction: Making a statement of what will happen in the future 

Hypothesis: An educated guess to what will happen