One of the main challenges of chemistry is to understand the connection between the macroscopic world that we experience and the microscopic world of atoms and molecules.
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ex: From a distance, a sandy beach looks like a single continuous "solid substance."
Up close however, a sandy beach consists of unique individual grains of sand.
And furthermore, each of these grains of sand are themselves individual silicon (Si) and oxygen (O) atoms connected by bonds.
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ex: The tremendous variety of substances in our universe are made from only ~120 different kinds of atoms.
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Similarly, there are 2 million words in the English language, yet all of them are generated from only 26 letters in the alphabet.
To understand the relationship between the macroscopic world and the microscopic world, and to study nature, scientists use a process called the Scientific Method.
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The 5 Steps of the Scientific Method
The Scientific Method = the process that lies at the center of scientific inquiry.
➞ There are 5 general steps in the process:
1. Making Observations. (Collecting Data)
a. Qualitative observations = describe characteristics.
b. Quantitative observations = "measurements" that involve both a number and a unit
2. Formulating a Hypothesis. (Making a Prediction)
Hypothesis = a possible explanation for an observation.
3. Testing the Hypothesis. (Performing Experiments)
Experiments usually always lead to new, unexpected observations, which brings the process back to step 1:
------ eventually...., a breakthrough...
4. Assembling Hypothesis into a Theory
Theory = an accepted explanation (or)
Theory = a set of tested hypotheses that gives an overall explanation of why nature is behaving a certain way.
5. Theory Becomes a Law
When a theory is observed in many different situations and is generally taken as fact rather than just an "accepted explanation," it becomes law.
Law = a factual summary of observed behavior
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** NOTE: Theories are just explanations of observed behavior. They are not accepted facts.
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Scientific Method Example
ex: Scientific Method (used in everyday life)...
You're a freshman in college and it's your very first day of class.
Let's assume the year is 1985, you're 18 years old, and you're truly a lost freshman.
You don't even know how to get to the university campus, smh...
First, you might buy a map (it's 1985, remember) and look up possible routes to campus.
Next, you could ask people familiar with the area about the advantages / disadvantages of the various routes on your map. (Making Observations and Collecting Data).
After gathering your information (data), you now predict the best route to campus. (Formulating a Hypothesis).
However, you can only find the best route by actually trying all of the routes and comparing the results. (Testing the Hypothesis and Assembling it Into a Theory).
Welcome to campus Freshie! 😊
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Next time in our discussion of SECTION 1 - Foundations of Chemistry,
We'll discuss SI Base Units and Uncertainty in Meassurement.