Question of the Day Tuesday, August 18 th, 2015 Is water an acid or a base? Why/How do you know?

Scientific Method is NOT the only way... The Scientific Method is a set of steps that explain how science happens in a perfect world The Scientific Method is a set of steps that explain how science happens in a perfect world As you know, the real world is not perfect, so science can happen in lots of other ways. As you know, the real world is not perfect, so science can happen in lots of other ways.

Perfect vs. Real

Example 1: Medicine Antibiotics were discovered by accident Antibiotics were discovered by accident A mold was causing bacteria near by to die A mold was causing bacteria near by to die

Example 2: X-Rays X-rays were discovered when a rock was left sitting on some film overnight. X-rays were discovered when a rock was left sitting on some film overnight. The rock gave off energy that left a mark on the film The rock gave off energy that left a mark on the film

Scientific Method in 4 Steps OBSERVE OBSERVE HYPOTHESIZE HYPOTHESIZE EXPERIMENT EXPERIMENT CONCLUDE CONCLUDE

O.H.E.C. Just Think... Just Think... “Oh, Heck!”

1) Observe Gather information using your 5 senses. Gather information using your 5 senses. Look for things that you cannot explain. Look for things that you cannot explain.

2) Hypothesize First, make an inference to explain what is happening. First, make an inference to explain what is happening. Next, turn that inference into a prediction that can be tested. Next, turn that inference into a prediction that can be tested. A hypothesis is best said as an A hypothesis is best said as an If... Then... Statement If... Then... Statement

Observations vs. Inferences

2) Hypothesize First, make an inference to explain what is happening. First, make an inference to explain what is happening. Next, turn that inference into a prediction that can be tested. Next, turn that inference into a prediction that can be tested. A hypothesis is best said as an A hypothesis is best said as an If... Then... Statement If... Then... Statement

Examples of If...Then... Statements If I give my plant fertilizer, then it will grow taller. If I give my plant fertilizer, then it will grow taller. If I wear body spray, then I will get more girls phone numbers. If I wear body spray, then I will get more girls phone numbers. If, then If, then.

3) Experiment An experiment is just a test of your prediction! An experiment is just a test of your prediction! 5kgyApYrY 5kgyApYrY 5kgyApYrY 5kgyApYrY

Variables (Flip to the very back page) Independent – what YOU change Dependent – dependent on what you change (independent variable) Constant How many variables at a time should you change in an experiment?

Independent and Dependent Variables If I give my plant fertilizer, then it will grow taller. If I give my plant fertilizer, then it will grow taller. If I wear body spray, then I will get more girls phone numbers. If I wear body spray, then I will get more girls phone numbers. If, then If, then.

4) Conclude If your prediction comes true, the hypothesis is accepted. If your prediction comes true, the hypothesis is accepted. This acceptance is temporary. Your hypothesis may be rejected when new evidence is collected. This acceptance is temporary. Your hypothesis may be rejected when new evidence is collected. If your prediction did not come true, modify your hypothesis and experiment again. If your prediction did not come true, modify your hypothesis and experiment again.

3 Types of Scientific Knowledge Knowledge gained by the scientific method can be expressed in 3 ways. Knowledge gained by the scientific method can be expressed in 3 ways. 1) Theories 1) Theories 2) Laws 2) Laws 3) Models 3) Models

Theory A theory is made by combining many tested inferences together. A theory is made by combining many tested inferences together. Theories are well-tested explanations, not wild guesses! Theories are well-tested explanations, not wild guesses!

Example 1: Theory of Evolution

Example 2: Kinetic Molecular Theory

Law A Scientific Law is an observation that has been tested so many times that we believe it is always true. A Scientific Law is an observation that has been tested so many times that we believe it is always true. A law says what happens, but does not explain why. A law says what happens, but does not explain why.

Example 1: Law of Gravity

Example 2: Boyle’s Law

Model A model is a representation of an object or idea. A model is a representation of an object or idea. Models can be visual or diagrams. Models can be visual or diagrams.

Example 1: Visual Model of DNA

Example 2: Diagram Model of Scientific Method

FINAL ANNOUNCEMENTS Homework is Spongebob Safety Story Homework is Spongebob Safety Story Quiz on Friday – don’t stress!! Quiz on Friday – don’t stress!!