Download Scientifc Method and Plants affecting soil

Methods of Scientists
WHAT IS SCIENTIFIC
INVESTIGATION?
Question Things
 Many realize that plants grow better in
certain soils. Soils can help plants to
grow.
 Can growing plants alter soil?
Hypothesize
 From prior knowledge, can you predict an
answer to my question?
 Try it now. Start like this
 If there are many containers of soil and
plants are put in half of them and allowed
to grow, then I think ……
Identify your Variables
 Independent Variable is the one thing you
deliberately change to see if it will have an impact on
something else.
 Dependent Variable is the one thing you measure to
see if it was impacted by the change in the
independent variable.
Write Your Procedure
 Design an experiment that will allow you to test your
hypothesis.
 Write the steps in sequence.



How much soil will you use?
How often will you water and with how much water?
What type of plant?
 Keep everything else exactly the same except the
independent variable. In this way, you will know if
that change had a measurable effect.
 Write down all the materials you will need in the
experiment
Data and Graphs
 Record your data into a table with headings and
units
 Calculate Averages and Deltas
 Graph the data appropriately (bar, line, circle)
page 18
 Independent Variable is on the X axis and
Dependent is on the Y
Analysis
 Examine your data in all of its forms.
 Look for trends and patterns
 Look for minimums and maximums
 DO NOT just repeat the data table but, rather,
explain what the data is telling you
 Make statements and show that the data supports
those statements
Conclusion
 Restate your hypothesis and then explain if the data
supports it or refutes it
 Summarize your findings
 In a new paragraph, explain if you found faults in
your design. Explain how they should be fixed.
Use Appropriate Measurements
 SI (System International or Metric)
 Length (meters)
 Mass (grams)
 Weight (Newton)
 Area (square meters or centimeters)
 Volume (cubic meters or cubic centimeters =
milliliters)
 Time (seconds or hours)
 Temperature (celsius or Kelvin)
 Density (mass/volume)
Things to Remember
 Mass is how much matter there is
 Weight is how gravity pulls on that matter
 Density is how much matter there is in a certain
amount of space. If I cut an object in half it still has
the same density because I reduced both its mass
and its volume.
 Temperature is a measure of the movement of atoms
or molecules. If it is so cold that atoms stop moving,
we call it absolute zero. That is 0 K or -273 C.
 It is often easier to work with extreme numbers by
using scientific notation.
Scientific Notation
 1 gram of H has 602000000000000000000000
atoms

 Use Scientific Notation to make it easy. Write the
number as a product of 2 numbers;
 a coefficient and 10 raised to a power
36,000 is 3.6 x 104
0.0081 = 8.1 x 10-3
STEPS
 1. the coefficient must be greater than or
equal to 1 and less than 10 (3.6)
 2. exponent indicates how many times the
coefficient must be multiplied by 10 (4)
 3. if the number is greater than 10, the
exponent is + and equals the number
 of places the decimal was moved to the left
(36,000 = 3.6 x 104)
 4. if the number is less than 10, the exponent
is - and indicates the number
 of places the original decimal point has been
moved to the right
Using Scientific Notation in Calculations
 1. Multiplication

multiply the coefficients and add the exponents

(3.0x104)x(2.0x102)=6.0x106
 2. Division

divide coefficients and subtract the exponents

(3.0x104)/(2.0x102)=1.5x102
 3. Addition & Subtraction

first make exponents the same then add or subtract the
coefficients
 (5.4x103 + 6.0x102)


5.4 x 103
 + 0.6 x 103

6.0 x 103
Practice
 You will now practice these skills.
Do Scientific Notation sheet
2. Convert between meters, kilometers and
centimeters on the next sheet
3. Tomorrow, you will set up an experiment to answer
the question “Do Plants Impact Soil?”
1.