1. Introduction to Science
Chapter 1

2. What is science? Science is the study of… Everything!!
A way of learning about the natural world.
Scientist: a person who studies, or has expert knowledge of a natural or physical science

3. Physical Science Physical Science: The study of matter and energy
Matter: the stuff the universe is made of
Energy: ability to do work
Two major classes of physical science
Chemistry: the study of interactions of matter
Physics: the study of motion and energy

4. Theories & Laws
Law: describes a process in nature that can be tested by repeated experiments
Based on facts and have been proven, If not supported by new information, the law is rejected
Law of Conservation of Energy
Theory: attempts to explain why these processes and observations are so.
Based on observations and can be tested, If new information if discovered, the theory is changed
Theory of Evolution
BOTH SUPPORTED BY EVIDENCE

5. Models & Technology Model: any representation of an object or a system
Technology: the application of science for practical purposes
We are surrounded by this daily!
Cathode Rays, CT Scans

6. Scientific Method
Method of organizing information and solving problems
Make an observation (use your 5 senses)
Ask a question
Research
Form a hypothesis (predict an outcome)
Experiment (test the hypothesis)
Analyze your results (record and organize your data)
Draw conclusion (was your prediction correct?)
Repeat your work and share it with others

7. Scientific Method Observation: I can’t wake up for school
Question: How can I get up on time?
Research: Go to bed earlier, set alarms, less technology before bed
Hypothesis: If I go to bed earlier, then I will be able to wake up.
Experiment: Try to go to bed earlier, and record if you get up earlier
Analyze your results: Did it work each day?
Draw conclusion: Did you confirm or disprove your hypothesis?
Repeat & Share: Always double check, tell someone about your discovery

8. Experiment
Experiment: a controlled procedure carried out to test a hypothesis
Variable: condition or trait you are testing (or changing)
Independent variable: this variable is manipulated by the experimenter, DOES NOT change in response to other variables
Dependent variable: the variable that changes in response to the independent variable, or being measured
Only ONE variable is tested in an experiment!!

9. experiment Control group: does not receive the variable
Experimental group: exposed to the independent variable, then compared to the control group
NO EXPERIMENT IS A FAILURE!
The results may help you discover something new even if they weren’t the results you wanted

10. data Qualitative: data that cannot be measured, it describes a quality
The softness of a cat’s fur, the color of the sky
Quantitative: data involving number, it shows a quantity
The age of your car, the hairs on your head

11. Lab Safety
Failure to follow lab safety rules will result in disciplinary consequences!

12. equipment
Metric Ruler: measures distance in centimeters, each line in between represents a millimeter (one tenth of a centimeter)
Graduated Cylinder: measures volume in milliliters
Meniscus: lowest point of the curve, read from here by putting your head at the same level

13. Measurement Math is the language of science
Scientists use the SI system (Systeme International d’Unites) because it is consistent
The SI system is based on the metric system and has BASE UNITS of measurement

14. Metric system
Measurements are made in specific units called BASE UNITS
Length: distance
Base Unit: meter (m)
Volume: amount of space something takes up
Base Unit: liter (L) for liquids, centimeters cubed (cm3) for solids
Mass: amount of matter in an object (not the same as weight)
Base Unit: gram (g)
Time: the amount of time something takes
Base Unit: second (s)
Temperature: how hot or cold something is
Base Unit: Celsius (°C) or Kelvin (K)

15. Metric system
Some measurements are too large or small to be measured in meters, liters, or grams so we add prefixes to them in order to avoid decimals and a lot of zeroes
Prefix: something added to the front of a word to change its meaning
Metric prefixes represent multiples of ten
Add the prefix symbol to the base unit symbol when writing a unit of measurement
kilo meter k m

16. Metric system
km = 1,000 meters

17. conversions Converting from one metric unit to the other
Write down - G’’ M’’ k H Da base d c m
Put your pencil on the given unit (km)
Move the necessary number of spaces to get to the desired unit (m)
In this case, 3 to the right
G’’ M’’ k H Da base d c m
Then move the decimal point from the original quantity the same amount
1 km = 1,000 m

18. conversions 387 g to kg 551 cm to m 398 ml to L 0.57 g to mg
58700 cm to km
0.387 kg
5.51 m
0.398 l
570 mg
.587 km

19. Graphs
Graphing is an important procedure used by scientists to display data collected during an experiment.
There are three types of graphs
Line, Bar, Pie
Each graph contains items that help you read the graph and understand the data being shown

20. Graphs
Line Graphs: Shows continuous change, and the relationship between two variables
Bar Graph: Show a comparison between similar items or events, or representing a single value for many items
Pie Graph: Show the parts of a whole, adds up to 100%

21. Graphs
Title: tells what the graph is about. It should be a concise statement placed above the graph.
Dependent variable: placed on the y-axis (vertical)
Independent variable: placed on the x- axis (horizontal)

22. graphs
Variable Scales: A scale is used so you know where to plot the points representing the data and must include all the data points.
The scales should start with 0 and increase by the same amount, your data will determine these values
Legend: a key to reading the data in your graph

23. Scientific Notation
Scientific notation is used to express really BIG or SMALL numbers more easily.
It is expressed as 2 factors:
Factor #1: a number between 1 and 10
Factor #2: a power of ten
x = 68,000
The exponent on 10 tells you the number of places to move to the decimal
If the exponent is positive, you move to the right
If it is negative, you move to the left

24. Quick conversions 6.7 x10-7 2.31 x105 5.79 x103 4.19 x10-5 .0065
94,100,000
9,840
231000
5790
6.5 x10-3
9.41 x107
6.5 x10-8
9.84 x103