Introduction to Chemistry The Scientific Method

Chemistry The study of chemistry investigates all substances and their changes The study of chemistry investigates all substances and their changes Looks at matter on a submicroscopic level Looks at matter on a submicroscopic level

Criteria of Science Consistent Consistent Observable Observable Natural Natural Predictable Predictable Testable Testable Tentative Tentative CONPTT for short CONPTT for short

Is it Science? Non-science – does not fit criteria of CONPTT (movie ratings) Non-science – does not fit criteria of CONPTT (movie ratings) False Science or Pseudoscience – claims to be a science does not fit CONPTT (astrology, phrenology) False Science or Pseudoscience – claims to be a science does not fit CONPTT (astrology, phrenology) Emerging science (Protoscience – fits most of CONPTT but not all Emerging science (Protoscience – fits most of CONPTT but not all Junk Science – Uses bad science Junk Science – Uses bad science

The Scientific Method Observation - gathering information through the senses. Observation - gathering information through the senses. Inference - a logical interpretation based upon prior knowledge or observations. Inference - a logical interpretation based upon prior knowledge or observations.

Hypothesis Scientific Hypothesis: A testable statement about the natural world (that can be used to construct more complex inferences and explanations – theories); e.g. Trout avoid warm waters Scientific Hypothesis: A testable statement about the natural world (that can be used to construct more complex inferences and explanations – theories); e.g. Trout avoid warm waters A hypothesis must be testable, and be able to be potentially proven right or wrong. A hypothesis must be testable, and be able to be potentially proven right or wrong.

Good or Bad Hypothesis Our universe is surrounded by another, larger universe, with which we can have absolutely no contact Our universe is surrounded by another, larger universe, with which we can have absolutely no contact

Good or Bad Hypothesis There are other inhabited planets in the universe There are other inhabited planets in the universe

Good or Bad Hypothesis Any two objects dropped from the same height above the surface of the earth will hit the ground at the same time, as long as air resistance is not a factor Any two objects dropped from the same height above the surface of the earth will hit the ground at the same time, as long as air resistance is not a factor

Scientific Method Experimental Procedures – Steps to test our hypothesis. Experimental Procedures – Steps to test our hypothesis. Results Results Conclusion - Revise your hypothesis and start over again. Conclusion - Revise your hypothesis and start over again.

Control & Variables Variable - part of the experiment that changes (this is what you are testing). Variable - part of the experiment that changes (this is what you are testing). –Independent Variable – Variable that is changed by the experimenter. –Dependant Variable – Variable that changes in response to the independant variable Control - standard for comparison. Control - standard for comparison.

Scientific Method Experimentation is the key to the Scientific Method. - Experiments are performed and data is collected. - Data is analyzed and compared to the existing hypothesis. - The hypothesis becomes a theory as data is applied and the theory is adjusted accordingly. - New experiments must be performed and the cycle continues.

Scientific Method After results are reproduced, scientific studies are published in journals. After results are reproduced, scientific studies are published in journals. Scientists review and critique published work. Scientists review and critique published work. Science is self correcting. Science is self correcting. Science is tentative. Science is tentative.

Scientific Theory Theory – well tested explanation that unifies a broad range of observations and scientific results. (atomic theory, cell theory) Theory – well tested explanation that unifies a broad range of observations and scientific results. (atomic theory, cell theory) Theories have strong predictive abilities (Plate tectonics). Theories have strong predictive abilities (Plate tectonics).

Overview of Scientific Method Scientific Law: A descriptive generalization about how some aspect of the natural world behaves under stated conditions; e.g., Dalton’s Law, Law of Thermodynamics, Newton’s Law of Universal Gravitation. Scientific Law: A descriptive generalization about how some aspect of the natural world behaves under stated conditions; e.g., Dalton’s Law, Law of Thermodynamics, Newton’s Law of Universal Gravitation.

Bad Example of the Scientific Method (IMHO) The book and documentary “Supersize Me” The book and documentary “Supersize Me” The experimentation was designed to insure the results that the experimenter wanted. The experimentation was designed to insure the results that the experimenter wanted.

Skepticism in Science It can be argued that Skepticism has contributed to great advances in Science and in fact are the basis for the ‘hero status’ that some scientists have. It can be argued that Skepticism has contributed to great advances in Science and in fact are the basis for the ‘hero status’ that some scientists have. A great example of this Nicolaus Copernicus. If he thought by consensus, he wouldn’t have come up with his theories which changed the world. A great example of this Nicolaus Copernicus. If he thought by consensus, he wouldn’t have come up with his theories which changed the world.

Consensus Science Science by its very nature is devoted to questioning the mainstream thoughts until substantial proof is delivered that follows the Scientific Method. Science by its very nature is devoted to questioning the mainstream thoughts until substantial proof is delivered that follows the Scientific Method. True Science shows all the facts and doesn’t allow itself to be altered. True Science shows all the facts and doesn’t allow itself to be altered.

The Scientific Method