Lesson 1.01 Flashcards
What does the field of chemistry study?
Chemistry is the study of the composition and structure of materials and the changes they undergo.
Define phenomena.
observable events or occurrences; plural of phenomenon
What is science?
It is generally agreed that for something to be considered science, it must be based on empirical observations, experimentation, and explanations based on logical reasoning.
What are empirical observations?
an observation verified by experimentation or experience rather than theory
Observable
Science attempts to explain natural phenomena by analyzing and observing the world and testing ideas about it.
Testable
Science must be able to answer a testable question using observation and experimentation. Investigations must produce empirical evidence that can be observed or measured to be considered science.
Replicable
Empirical evidence can be replicated, or reproduced, and verified by other scientists if they conduct the same tests under the same conditions.
Reliable
The more an experiment is repeated, with the same outcomes, the more reliable the evidence becomes. Evidence without bias also increases its reliability.
Flexible
Science is an ever-changing body of knowledge as new observations are made through experimentation. As new information is discovered, new evidence can add to current evidence, allowing scientists to improve their theories.
What is bias?
a prejudice in favor of or against one thing, person, or group
What are two things you can look for to determine if a question can be answered by science?
empirical observations and reasonable logic.
What are some examples of testable and non-testable questions?
Testable:
How long does it take water to freeze?
Non-testable:
Why do you think the environment is important?
Question: What type of question can the scientific method attempt to answer?
“What prevents the grass from growing in this spot?”
Research: Why is it useful to do background research before you write and test a hypothesis?
For instance, there may be previous experiments conducted on dead spots found in lawns. You might want to research these experiments to find reasons why grass can stop growing.
Hypothesis: What is a hypothesis, and why is it important to a scientific investigation?
A hypothesis is a prediction or a tentative explanation based on some research or observation. They are tentative explanations and allow for variables to be tested.
Test: Describe the test (experiment) step of the scientific method.
An experiment allows you to test your hypothesis to determine if it is a correct or incorrect prediction of the outcome. There are many ways to test a hypothesis, but every experiment should have at least one variable that changes while the others stay the same, or are controlled.
What is an independent variable? Give some examples from hypotheses and investigations.
The independent variable is the factor the scientist has chosen to change in an experiment. In the example experiment, the pH of the soil is the independent variable.
What is a dependent variable? Give some examples from hypotheses and investigations.
The dependent variable is the factor that changes in response to the independent variable in an experiment. In the example experiment, grass growth is the dependent variable.
What are controlled variables, and why are they important?
Controlled variables are the factors a scientist chooses to keep constant over the course of an experiment. In the example experiment, factors like temperature, water, and exposure to sunlight must be kept constant
Analysis: Describe how results are analyzed after an experiment.
Based on the results of your experiment, you may be able to determine if the high pH of the soil prevented the patch of grass from growing.
What is inference? Where in the scientific method do you make inferences?
An inference is a conclusion derived from evidence and logical reasoning. Once an experiment is complete, the results need to be analyzed to determine if the outcome supports the hypothesis.
