General Chemistry Unit 1: Chapter 2 Scientific Inquiry General Chemistry Unit 1: Chapter 2

Learning Objectives Identify what Science is and its goals Apply the scientific method and variables Compare and contrast a hypothesis, theory, and law in science. Define chemistry Explain what the different branches of chemistry are and their importance

What is Science? Which of these are true about science? A – A set of facts B – A way of thinking C- An explanation of the natural world around us D – Is based on experimentation E - Is never changing F – Is constantly changing G – is based on personal beliefs

Goals of Science to provide natural explanations understand patterns in nature make useful predictions

Science is an organized way of gathering and analyzing evidence about the natural world. Scientific ideas are open to testing, discussion, and revision.

What is Chemistry? Chemistry is the study of matter and the changes it undergoes.

Branches of Chemistry Many major areas of study for specialization Several career opportunities Also used in many other jobs

1. Organic Chemistry Organic is the study of matter that contains carbon Organic chemists study the structure, function, synthesis, and identity of carbon compounds Useful in petroleum industry, pharmaceuticals, polymers

2. Inorganic Chemistry Inorganic is the study of matter that does NOT contain carbon Inorganic chemists study the structure, function, synthesis, and identity of non-carbon compounds Polymers, Metallurgy

3. Biochemistry Biochemistry is the study of chemistry in living things Cross between biology and chemistry Pharmaceuticals and genetics

HONK if you passed p-chem 4. Physical Chemistry HONK if you passed p-chem Physical chemistry is the physics of chemistry… the forces of matter Much of p-chem is computational Develop theoretical ideas for new compounds

5. Analytical Chemistry Analytical chemistry is the study of high precision measurement Find composition and identity of chemicals Forensics, quality control, medical tests

The Scientific Method

THE SCIENTIFIC METHOD is a way to organize your thinking. Make Observations Question Collect Research Hypothesis – If and then statement Experiment – only one variable!!! All other conditions controlled!!! Identify your variables Conclusion – Analyze your data and state whether you hypotheses has been disproven or not. Using the Scientific Method to improve your social life.

Identifying Variables Independent/Maniupated Variable – what is being tested in the experiment Dependent Variable/Responding Variable – changes in response to the independent variable Control Variable/constants – variables that do not change throughout the experiment

Identifying Groups Experimental Group – This is the group that has the independent variable being acted upon them. Control Group – This is the group that does NOT have the independent variable acting upon them.

Two Types of Observations Observing means using one or more senses to gather information. Two Types: Quantitative observation  involves numbers. Example : Qualitative observation describing what you see; doesn’t involve numbers. Example:

Hypotheses A hypothesis is a possible explanation based on facts and observations A Hypothesis must always be : If and then statement Testable Can never be proven to be correct, can only be disproven

Laws, Theories and Hypotheses Hypothesis Theory Law An educated guess that is based on observations, not yet supported by scientific testing and evidence. Ex… If a phone releases high amount of infrared radiation, then phones cause cancer. Scientific  theories summarizes a hypothesis or group of hypotheses that have been supported with repeated testing -A theory is valid as long as there is no evidence to dispute it. -Ex…Theory of natural selection A theory that has withstood the test of time Repeatedly supported over a long period of time by testing and evidence. - Ex…Law of gravitation Laws, Theories and Hypotheses A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing A theory is valid as long as there is no evidence to dispute it. Theory of natural selection A law generalizes a body of observations. A scientific theory can become a law when it withstands the tests of time and is never disproven. Example: law of gravity