Chapter 1

Introduction to Science

Science: a system of knowledge based on facts or principles

Science is observing, studying, and experimenting to find the nature of things.◦Science requires investigation, experimentation, and

observation.

What is Science?

Scientific Theory - a tested possible explanation of a natural event.

A Scientific Theory must pass several tests1. It must explain an observation simply and clearly. 2. Experiments that test a theory must be repeatable.3. You must be able to use a scientific theory to predict

what might happen in a slightly different scenario.

Scientific Theories and Laws

Scientific Law – a summary of an observed natural event. A scientific law does not try to explain why something is happening, just that it does happen.

Scientific theories and laws are NOT absolute!! They can be modified as new advances are made.

Example: the Earth is Flat.

Science is characterized by uncertainty, and is always changing.

Scientists must be able to observe and test a subject.

Hypothesis- Is a possible explanation for an event or set of observation.

A scientific hypothesis can always be tested by examining evidence.

A hypothesis is not always correct.

A scientific investigation begins with an observation and a question that can be tested.

Observations are made through one or more of the five senses.

Instruments, like microscopes or binoculars, are used to let scientists observe things that they could not normally detect through the sense.

Science Skills and Methods

An experiment procedure that tests a hypothesis by the process of collecting information under controlled conditions.

1st you must have a variable. A variable is any factor that can influence the

outcome of an experiment.

Designing an experiment

The variable determines the difference between the experimental setup and the control setup.

The setup with the variable is the experimental setup.

The setup from which the variable is missing is the control.

All other variables must be kept the same!!

A prediction uses what is called deductive reasoning.

A prediction is made in the form of an “If….then….” statement.

Analyzing data is the process of determining whether data is reliable and whether it supports of refutes a given prediction or hypothesis.

Inferring is the process of drawing conclusions on the basis of facts.

If the results are consistent with the hypothesis, it can be concluded that the hypothesis is supported by the experiment.

One experiment is not enough to make scientists confident of a hypothesis.