Describe how Lavoisier transformed chemistry Identify the steps in the scientific method Explain why collaboration and communication are important in science
Scientific method Observation Hypothesis Experiment Manipulated variable Responding variable Theory Scientific law
Alchemy: was the study of matter that came before chemistry It rose from many different regions of the ancient world and was practiced as early as 400 B.C. It had two sides: practical & mystical Practical alchemy focused on developing techniques for working with metals, glass, & dyes Mystical alchemy focused on concepts like turning lead into gold
Ultimately, alchemists developed the tools and techniques for working with chemicals Alchemists developed processes for separating mixtures and purifying chemicals They designed equipment such as: beakers, flasks, tongs, funnels, and the mortar & pestle
By the 1500’s alchemy was a thing of the past and science flourished In the 1600’s, the Royal Society of London for the Promotion of Natural Knowledge, the first scientific organization, was formed They met to discuss scientific topics and conduct experiments The society’s aim was to encourage scientists to base their conclusions about the natural world on experimental evidence
Famous chemist of the 1700’s in France He helped to transform chemistry from a science of observation to a science of measurement He designed a balance to measure mass to the nearest gram He also through experimentation proved how things burn As brilliant as he was, it did not save him from the revolutionary guillotine
Is a logical systematic approach to the solution of a scientific problem Steps in the scientific method: Making observations Forming a hypothesis Testing a hypothesis Drawing conclusions Communicating results They Might be Giants: Scientific Method Song They Might be Giants: Scientific Method Song Monty Python demos the scientific method Monty Python demos the scientific method Big Bang Theory: Scientific Method Big Bang Theory: Scientific Method
Requires using your senses to obtain information This information can then lead to a question to be answered For example, while on vacation in Alaska you observed the aurora borealis This leads you to ask “What causes the different colors of light?”
Using our previous example, we proposed that the different colors of light are due to different gases. Coming up with a possible explanation for an observation is called a hypothesis The procedure for testing a hypothesis is called an experiment When we design an experiment, we have to deal with variables, or factors that change What could we do for an experiment to test our hypothesis?
Manipulated Is the variable you change in an experiment Also called the independent variable What would our manipulated variable be? Responding Is the variable you observe during the experiment Also called the dependent variable What would our responding variable be?
Once a hypothesis meets the test of repeated experimentation, it may become a theory A theory is a well tested explanation for a broad set of observations For example: chemistry’s focus is the fundamental structure of matter theory Theories allow us to predict the behavior of matter or visualize processes that we can not see Theories can change and can be disproved
A scientific law is a concise statement that summarizes the results of many observations and experiments For example: we will discuss the gas laws A law doesn’t try to explain the relationship it describes A theory is required for an explanation
Collaboration Is the joining of scientists, usually from different areas of expertise to solve a problem It is a practical choice since no one is an expert in everything However, it isn’t always a smooth process Communication Is essential for sharing scientific ideas with other scientists as well as the public The methods have changed with the development of technology However, scientist still publish their work in scientific journals