pre-class activity 9/5
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Pre-class Activity 9/5. Chemistry is the study of matter and the changes that it undergoes. What is matter? Be prepared to give two examples of matter that can be found in the classroom. Chemistry and Matter. Chemistry is the study of matter and the changes that it undergoes. - PowerPoint PPT PresentationTRANSCRIPT
Pre-class Activity 9/5
Chemistry is the study of matter and the changes that it undergoes.
What is matter? Be prepared to give two examples of matter that can be found in the classroom
Chemistry and Matter
Chemistry is the study of matter and the changes that it undergoes.
Anything that has mass and takes up space
A measurement that reflects the amount of matter
Questions
What in the universe isn’t matter?Energy
Why aren’t the terms mass and weight interchangeable?
Weight is not only a measure of the amount of matter, but also a measure of the effect that gravity has on matter
Scientific Method – A Systematic Approach
OBSERVATION HYPOTHESIS EXPERIMENT THEORY
Draw conclusions and revise hypothesis
Theories are supported by many
experiments
Observations
Hot 300o
Qualitative vs. Quantitative
Temperature
Height
Mass
Length
Pre-class Activity 9/8 A scientist owns fish that are very sensitive to
changes in temperature. One morning, after a huge storm, he came into the lab only to find that all the fish in his tank were dead. He suspected that there might have been a power outage due to the storm, in which the power to the heater may have been interrupted. To test this, he measured the temperature of the tank, only to find that it is normal.
Identify the observation, hypothesis and experiment in the paragraph above. Does the result of the experiment support the hypothesis?
Homework: Read Scientific Method and the Milk Lab, continue with HW assignments 1,2,3. Homework Assessment #1 – Wednesday 9/10
Mrs. Pav’s Milk Lab Write-Up
Pupose: To determine if the type of milk affects the migration time of food coloring in the milk experiment
Hypothesis: If whole milk is substituted for skim milk in the milk experiment, the food coloring will migrate slower.
Materials: In addition to materials listed for the milk lab, whole milk was added
Procedure: Refer to written procedure for the milk lab. The migration time of food coloring was measured by using a stop watch to record the time that it took for the food coloring to migrate to the edge of the petri dish.
Results: The time for the control (skim milk) was 4.8 seconds. The time for the experimental group (whole milk) was 3.2 seconds.
Conclusions: The hypothesis was confirmed by the data because the migration time of food coloring increased for whole milk as compared to skim milk
ExperimentsA set of controlled observations that test a hypothesis.
Key Terms
Variable: A quantity or condition that can have more than one value
Independent Variable: A variable that is changed by the investigator in an experiment
Dependent Variable: A variable the changes in response to the independent variable
Control: A standard for comparison
Experimental Design Example
The Effect of Temperature on the Respiration Rate of Fish
Temp (oC)
Res
pira
tion
Rat
e
What is the dependent variable?
What is the independent variable?
What would be an appropriate control?
What is the relationship between respiration rate and Temperature?
Theory vs. Scientific Law
Theories are explanations that are supported by many experiments
Scientific Law describes a relationship in nature that is supported by many experiments
Pure vs. Applied Research
Gaining knowledge for the sake of knowledge
Vs.
Gaining knowledge to solve a specific problem
TOP 3 CHOICES FOR LAB PARTNERS
COOPERATIVE CONSCIENCIOUS RELIABLE
SOMEONE TO WORK WELL WITH
CONSCIENCIOUS RELIABLE A SUCKER
SOMEONE TO DO ALL THE WORK
DEVIANT MISCHIEVIOUS STAYING AFTER SCHOOL TO
WASH GLASSWARE
SOMEONE TO GOOF OFF WITH
CREDITS
DIRECTION AND PHOTOGRAPHY……………MRS. PAV
SCIENTIST, SLACKER AND
MISCHIEF MONKEY #1………………………….GARCIA PAV
SCIENTIST, SUCKER AND
MISCHIEF MONKEY #2…………………………OLIVIA PAV