Chapter 1: Introduction to Science

• 1.1 The Nature of Science

• 1.2 The Way Science Works

• 1.3 Organizing Data

Vocabulary:

• Critical Thinking• Scientific method• Variable• Length• Mass• Volume• Weight

Important Science Skills:

• Identifying problems• Planning experiments• Recording observations• Reporting & analyzing data• Learning to think like a scientist• Thinking critically

• Critical thinking: applying logic and reason to solve problems

Scientific Method: a process used to solve problems

Observe: Make an observation about anything in nature.

State a problem/ form a question: What do you want to know?

Collect data: Information that you already know

Form a hypothesis: An educated guess or possible answer to your question or problem.

Experiment: Test your hypothesis

Collect data: Make observations from your experiment

Draw a conclusion: Did your hypothesis turn out to be true?

If not, modify hypothesis based on observations.

Scientific Method

• Used by EVERYONE, not just scientists!• There is no single scientific method: it is a

way of thinking rather than an exact path for scientists to follow.

• No experiment is a failure!• Every experiment provides observations &

information about our natural world. • Think of Roentgen who accidentally discovered x-

rays.

Experimental Parts:

• Control: part of experiment that stays unchanged; considered “normal”

• Variable: part of experiment that varies. Test only 1 variable at a time.• Why? Otherwise, it is

harder to make reliable conclusions.

Types of Variables

1. Independent variable: variable that changes to see what happens

2. Dependent variable: depends on independent variable; may change because of independent variable.

• Example: The size of tomatoes depends on the amount of sun they receive.

• Independent variable: Amount of sun• Dependent variable: Size of tomatoes

Units of Measurement:

• Scientists use the International System of Units (abbreviated SI units)• Why? Then, no

matter where you are in the world, sharing data is much easier for scientists.

SI Base Units:Quantity Unit Abbreviation

Length Meter m

Mass Kilogram kg

Time Seconds s

Temperature Kelvin K

Electric Current

Ampere A

Amount of substance

Mole mol

Volume Cubic meter m3

SI Base Units (continued)

Other Units

Millimeter (mm), centimeter (cm), inch (in), feet

Gram (g), milligram (mg)

Millisecond (ms), minute (min), hour (hr)

Fahrenheit (°F), Celsius (°C)

Milliampere (mA)

Millimole (mmol)

Cubic centimeter (cm3), milliliter (mL), liter (L)

Making Measurements:

• Length: straight line distance between 2 points

• Mass: amount of matter in an object• Volume: how much space something

takes up• Weight: force with which gravity pulls on

matter