Copy the objectives and agenda into your daily work organizer, then complete the Catalyst.

Catalyst (Do Now): On your daily work organizer, make at least 5 observations

about this picture. Use complete sentences.

 

Observations, Inferences, and the Scientific Method

August 8, 2012Chemistry

Let Your Goals Guide You…• Today is the first day of academic work.• Some of your goals are…

– “to get straight A’s”– “to pass all my classes”– “do my best”– “go to college” – UCLA, USC, etc.– “become a professional…” - basketball player,

surgeon, OBGYN, auto/civil/structural engineer, etc.

• Remember your goals as you work hard today!

Objectives

• I can compare and contrast quantitative observations, qualitative observations, and inferences.

• I can identify the six steps of the scientific method in sequence.

Agenda

• Catalyst• Observations and Inferences Demonstration• Introduction to the Scientific Method• Scientific Method Case Study• Exit Slip

Observations

Definition: actually witnessed• Qualitative

– Use of senses (Ex: This coffee is hot.)• Quantitative

– Numbers and measurements (Ex: This coffee is 160°F.)

InferencesDefinition: an explanation based on background

information and experience. An interpretation of an observation

Ex: It must be around 7 a.m. because Ms. Boon is drinking coffee. The inference that it’s around 7 a.m. is based on observations made

in the past that when Ms. Boon is drinking coffee, it is the morning.

Demonstration: Practice Making Observations

Quantitative Observations Qualitative Observations

Demonstration Debrief

• Circle your observations that are actually inferences.

The Scientific Method: 6 Steps

1 •Question

2 •Hypothesis

3 •Procedure

4 •Data

5 •Analysis

6 •Conclusion

An every-day working method

• Scenario: – You arrive at home at night, try to switch on the light and

nothing happens…..• Hypothesis:

– You guess that …..is going on• Experiment Procedure and Data Gathering

– You come up with a plan and test your guess• Analysis

– Did it work? Or not• Conclusions

– And what next?

Before the Experiment

1. Investigative Question: – Observation: Identify a problem

interesting to you.– What do you want to know or

explain?2. Hypothesis:

– What do you think will happen?– Prediction, guess an explanation

for the problem– Needs to be testable

The Experiment

3. Procedure: Design an experiment.• Plan: How will you test your hypothesis?• Materials: what do you need to test the

hypothesis?• Procedure: a step by step plan of your

investigation• Safety Rules: the precautions to be followed

during the experiment

4. Data: Perform the experiment– Follow your plan– Collect and record the data

After the Experiment5. Analysis

• Look at the data, organize them (data tables, graphs)

• Are the data consistent and reliable?• Compare data to your hypothesis

6. Conclusions• Reflect on your analysis • Does the experiment address the problem?• Do the data support or contradict your

hypothesis?• Can you extend your observations to other

situations?• Do you need more experiments to prove or

disprove your hypothesis?• Are there alternative explanations?

What if your data do not support your hypothesis?

A. The experiment was a waste of timeB. The experiment had flaws, redesign it and do

the new experimentC. The experiment went well, so repeat it again

and again until it supports your hypothesisD. The experiment went well. Use the collected

data to change hypothesis and design new experiment to test it.

Practice: Scientific Method• Worksheet 1: “The Strange Case of BeriBeri”

• Worksheet 2: More Scientific Method Practice

• Worksheet 3 (Homework): How Penicillin was discovered

Exit Slip 1: Observations and Scientific Method

• Put all your materials away except for a pencil or pen.

• Work silently on the exit slip.• When you are done, turn over your exit slip

and wait silently.