1. Chapter 1 Science Skills
Mr. Bruder

2. What is Science? Science is what scientists do
Science is trying to explain the world around us
Science is a way of thinking
“Science is a system of knowledge based on facts or principles
Book talks about “social science”
We prefer social studies

3. Branches of Science Science Biological Science Earth Science Physical

4. Branches of Science Science Biological Science Earth Science Physical
Zoology
Botany
Science of living things
Ecology

5. Branches of Science Science Biological Science Earth Science Physical
Physics
Chemistry
Science of matter and energy

6. Branches of Science Science Biological Science Earth Science Physical
Geology
Meteorology
The systems of the earth
Astronomy

7. Branches of Science
There are many more branches to biological and earth sciences
The three categories overlap
Biochemistry
Astrobiology
Geophysics

8. What is Chemistry?
The study of matter, its composition, properties, and the changes it undergoes
Applied Chemistry is the using of chemistry to attain certain goals, in fields like medicine, agriculture, and manufacturing
Pure Chemistry gathers knowledge for knowledge sake

9. Which Comes First? Applied Chemistry Pure Chemistry
usually comes first, applied later
Called technology
Or engineering
Pure chemistry can explain behavior that has been used without knowing why
Steel swords
Can’t be good or bad
Can be good or bad depending on use

10. Chemistry is A natural science A language with its own vocabulary
A way of thinking

11. Branches of Chemistry
Analytical Chemistry -studies composition of substances.
Organic Chemistry -compounds containing carbon
Inorganic Chemistry -substances without carbon
Biochemistry- Chemistry of living things
Physical Chemistry studies behavior of substances
rates and mechanisms of reactions
energy transfers

12. Science From Curiosity
Science begins with curiosity and often ends with discovery.
How or Why is this possible?
Curiosity provides questions but is seldom enough to achieve scientific results.
Then how do we achieve these results?

13. Observations Qualitative – describe with words
Hot , red, large
Quantitative – describe with numbers
100° , 10 meters, 3.46 grams
Scientists prefer quantitative
Easy to agree upon
No personal bias

14. Models A representation of some object or event
Made to better understand it
Often used if real thing is too big, small or complex.
Come in a variety of forms
Physical models
Diagrams
Computer models

15. The Scientific Method A way of thinking about and solving problems
It is a logical method
You do it all the time

16. Scientific Method A way of solving problems or answering questions
Starts with observation- noting and recording facts
Hypothesis- an educated guess as to the cause of the problem or answer to the question

17. Scientific Method Experiment- designed to test the hypothesis
Only two possible answers
1) hypothesis is right
2) hypothesis is wrong
Generates data observations from experiments
Modify hypothesis- repeat the cycle

18. The Scientific Method
Does not always work this way, but gives a way of guiding our thinking
Hard part is testing only one variable at a time.
Changing only one thing at a time
If you change more than one, you don’t know which one is the cause

19. Variables
Controlled experiment- Only want one thing to change at a time in a laboratory.
Manipulated variable- What you change or control directly
Also called independent variable
Responding variable – What changes as a result. No direct control
Also called dependent variable

20. Observations Hypothesis Experiment Cycle repeats many times.
The hypothesis gets more and more certain.
Becomes a theory
A thoroughly tested model that explains why things behave a certain way.
Observations
Hypothesis
Experiment

21. Theory can never be proven.
Useful because they predict behavior
Help us form mental pictures of processes (models)
Observations
Hypothesis
Experiment

22. Another outcome is that certain behavior is repeated many times
Scientific Law is developed
Description of how things behave
Law - how
Theory- why
Observations
Hypothesis
Experiment

23. Law Modify Observations Theory (Model) Hypothesis Experiment
Prediction
Modify
Experiment
Experiment
Law

24. Law vs. Theory Law Theory Describes how Explains why
Summarizes observations
Agrees with observations
Usually an equation
Predicts new discoveries

25. Law vs. Theory
Theory can’t be proved; always the possibility that a new experiment will disprove a theory
Law described a natural phenomenon, but does not attempt to explain it

26. Measurement How do we measure in science? What do measurements mean?
How do we tell?
Let’s start with Accuracy vs. Precision

27. How good are the measurements?
Scientists use two words to describe how good the measurements are-
Accuracy- how close the measurement is to the actual value
Precision- how well can the measurement be repeated

28. Differences
Accuracy can be true of an individual measurement or the average of several
Precision requires several measurements before anything can be said about it

29. Let’s use a golf anaolgy

30. Accurate? No
Precise?
Yes

31. Accurate?
Yes
Precise?
Yes

32. Precise? No
Accurate?
Maybe?

33. Accurate?
Yes
Precise?
We cant say!

34. Examples Multiple Measurements Correct Repeatable Reproducible
Single Measurement
True Value

35. Scientific Notation
To write in Scientific Notation you need a number between 1 & 9 in front of the decimal.
When going from right to left you add the exponent (positive exponent)
When going from left to right you subtract the exponent (negative exponent)

36. Converting Cont.
Examples
345
56890

37. The Metric System

38. Measuring The numbers are only half of a measurement It is 10 long
10 What?????
Numbers without units are meaningless

39. The Metric System Easier to use because it is a decimal system
Every conversion is by some power of 10
A metric unit has two parts
A prefix and a base unit
Prefix tells you how many times to divide or multiply by 10

40. Base Units Length - meter more than a yard - m
Mass - grams - a bout a raisin - g
Time - second - s
Temperature - Kelvin or ºCelsius K or C
Energy - Joules- J
Volume - Liter - half f a two liter bottle- L
Amount of substance - mole - mol

41. Prefixes kilo k 1000 times deci d 1/10 centi c 1/100 milli m 1/1000
kilometer - about 0.6 miles
centimeter - less than half an inch
millimeter - the width of a paper clip wire

42. Volume Calculated by multiplying L x W x H
A liter volume of a cube 1 dm (10cm) on a side….
So 1L = 10cm x 10cm x 10cm
1L = 1000cm3
1/1000L = 1 cm3
1mL = 1cm3

43. Mass Weight is a force. Mass is the amount of matter.
1g is defined as the mass of 1 cm3 of water at 4 0C.
1000g = 1000 cm3 of water
1kg = 1L of water

44. Converting k h D d c m
how far you have to move on this chart, tells you how far, and which direction to move the decimal place.
The box is the base unit, meters, Liters, grams, etc.

45. k h D d c m Conversions 5 6 Change 5.6 m to millimeters
starts at the base unit and move three to the right.
move the decimal point three to the right 5 6

46. k h D d c m Conversions convert 25 mg to grams convert 0.45 km to mm
convert 35 mL to liters
It works because the math works, we are dividing or multiplying by 10 the correct number of times

47. Conversions k h D d c m
Change 5.6 km to millimeters

48. Which is heavier?
it depends

49. Density How heavy something is for its size
The ratio of mass to volume for a substance
D = M/V
Independent of how much of it you have
Gold- high density
Air- low density

50. Calculating The formula tells you how Units will be g/ml or g/cm3
A piece of wood has a mass of 11.2g and a volume of 23mL. What is the density?
A piece of wood has a density of 0.93 g/mL and a volume of 23 mL what is the mass?

51. Floating Lower density floats on higher density
Ice is less dense than water
Most wood is less dense than water
Helium is less dense than air.
A ship is less dense than water

52. Density of Water 1g of water is 1mL of water
Density of water is 1 g/mL
At 40C
Otherwise it is less

53. Measuring Temperature
0ºC
Celsius scale.
water freezes at 0ºC
water boils at 100ºC
body temperature 37ºC
room temperature ºC

54. Measuring Temperature
273 K
Kelvin starts at absolute zero (-273 º C)
degrees are the same size
C = K -273
K = C + 273
Kelvin is always bigger.
Kelvin can never be negative.

55. Temperature A measure of the average kinetic energy
Different temperature scales, all are talking about the same height of mercury.
Derive a equation for converting ºF toºC

56. Calculating Temp. From Celsius to Fahrenheit F= (C x 9/5) + 32
From Fahrenheit to Celsius
C= 5/9 (F-32)
Examples:
49 0F to 0C
97 0C to 0F

57. Converting Kelvin Converting Kelvin to Celsius K = C + 273
Converting Celsius to Kelvin
C = K – 273
Why is there no conversion from Kelvin to Fahrenheit?

58. Problems
How many????
349K to 0C
120C to K
340F to 0C
1010C to 0F

59. Temperature is different
from heat.
Temperature is which way heat will flow. (from hot to cold)
Heat is energy, ability to do work.
A drop of boiling water hurts,
kilogram of boiling water kills.