Thursday, October 25, 2012

Eaarth Science - Volume of a drop


 

Instructions:  DO NOT WRITE ON THIS HAND OUT!  You and your tablemates will be practicing the steps of the scientific method, conducting an experiment and writing-up a lab. 

·       On a separate sheet of paper write the names of the members of your table that actively help with all parts of the mini-lab; this will be your lab write-up.

·       Write out the question I gave you below, include the label Question:

·       Write our Hypothesis: and then your educated guess to answer the question.  Remember to discuss with your tablemates about how to make an educated guess then record the hypothesis on your lab write-up.

·       Continue writing the label for each step (Q, H, T, M, P, D, A, & C) and following my hints for each step.

 

Question:  How much space (volume) does a drop of water take up?

 

Hypothesis:  What is your educated guess to answer the question? Compare 1 drop to 1 mL of water.

 

Materials:  Every item used for data collection

 

Procedures: Step by step directions of your experiment that include diagrams that help illustrate your procedures

 

Data table:  Have room to include ten trials, Yes, do the experiment ten times, make sure everyone in your group has an opportunity to collect data by doing the experiment.

 

Analysis:    Show an example of how calculated the volume of a drop, in mL. Also show an example of how calculated the average volume of a drop, in mL, for the trials you did. Create a data table showing the average drop # for all other groups in the class.

 

Conclusion:         Restate your hypothesis. Did you answer the question?

                    How do your results compare to the other tables?  Explain.

How might error have occurred in your experiment?  What affect might it have had?  How can you redo your experiment to attain more accurate

results?

                   

Bonus Points:  if you finish both mini-labs early, you may earn bonus points for conducting a next step to this experiment.  You are limited to the materials provided or on your person.  You may also include a graph(s) of your data for e.c.

Friday, October 19, 2012

Earth science- Drops on a Penny


Instructions:  DO NOT WRITE ON THIS HAND OUT!  You and your groupmates will be practicing the steps of the scientific method, conducting an experiment and writing-up a lab. 

·       On a separate sheet of paper (NOT in the notebook) write the names of the members of your table that actively help with all parts of the mini-lab; this will be your lab write-up.

·       Write out the question I gave you below, include the label Question:

·       Write our Hypothesis: and then your educated guess to answer the question.  Remember to discuss with your tablemates about how to make an educated guess then record the hypothesis on your lab write-up.

·       Continue writing the label for each step (Q, H, M, P, D & C) and following my hints for each step.

 

Question:  How many drops of water can a penny hold?

 

Hypothesis:  What is your educated guess to answer the question?  You may compare a penny next to a single drop to help you with this.

 

Materials:  Record every item used for data collection

 

Procedures: Record Step by step directions of how you used each material listed in your experiment to find your answer, include diagrams that help illustrate complex  procedures. Final  procedures should be more complex than those listed in your RD.

 

Data table:  Have room to include ten trials of data collection.  Yes, do the experiment ten times, (5 trails per person) make sure everyone in your group has an opportunity to collect data by doing the experiment.

 

Analysis:    Show an example of you calculated the average  # of drops for the trials you did. Create a data table showing the average drop # for your group. Make a bar graph of your trails and the average # of drops.

 

Conclusion:         This should be in para graph form and not just answers to the following questions

Did you answer the question?   Do your results compare to the other tables?  Explain.  How might error have occurred in your experiment?  How can you redo your experiment to attain more accurate results?

 

Wednesday, October 17, 2012

Earth Science- Scientific -vs- research questions


Group Practice:  are the following SQ or RQ, if it is a research question re-write it as a scientific question.  Everyone should record this practice in their notes.

  1. How do waves travel faster on calm or windy days?
  2. What do hawks around campus eat?
  3. Why do cats have fleas?
  4. Which grade level at OHS litters most?
  5. Which cars in the parking lots are most expensive?
  6. Does the speed of sound change with the weather?

 

Balancing Chemical Reactions


Balance the following:

      1. K + F2     KF
      2. CH4 + O2    CO2  +  H2 O
      3. Ca  +  H2 O    Ca(OH) 2   +  H2
      4. ZnO  +  HCl    ZnCl2  +  H2 O
      5. KClO3  KCl  +  O2
hint: Cl = chloride

SQ vs RQ and Questions for wtiting Hypothesis

10/15/2012
Group Practice:  are the following SQ or RQ, if it is a research question re-write it as a scientific question.  Everyone should record this practice in their notes.

  1. How do waves travel faster on calm or windy days?
  2. What do hawks around campus eat?
  3. Why do cats have fleas?
  4. Which grade level at OHS litters most?
  5. Which cars in the parking lots are most expensive?
  6. Does the speed of sound change with the weather?

10/17/2012
A.     Underline the variables (independent & dependent) in each of the scientific questions you wrote earlier.

B.  For each question use your prior knowledge and experience to come up with an Hypothesis = expected answer to each question and underline the variables

2. Question: How does the amount of energy that hits the Earth in the form of light rays relate to the angle at which those rays strike (latitude)?

3. Question: Does rainfall influence the distribution of different biomes such deserts, grasslands, and forests?        '

4. Question: Does the extinction of a predator species result in a faster rate population growth in the prey species?

5. Question: Is plant cover related to soil erosion?

 

Friday, October 12, 2012

physical/chemical changes investigation


Physical and Chemical Changes Investigation Lab


Background Information


Matter is constantly changing. The two kinds of changes that occur in matter are physical and chemical changes. In a physical change, no new substances are formed. However, physical properties such as size, shape, color, or phase may change. Dissolving, melting, evaporating, and grinding are examples of physical change.

As a result of chemical change, one or more "new" substances with new and different properties are formed. The new substances are different from the original substance. Burning and the rusting of iron are examples of chemical change.

Problem


What are the differences between physical and chemical changes?

 


Materials (per student)


Votive candle
Scoop
Test-tube rack
Aluminum foil ~(15 cm x 15 cm)
Magnesium ribbon (1 cm long)
Test-tube clamp
Small piece of paper
1 M hydrochloric acid
Matches
Watch glass
Safety goggles
Table salt
Sand
2 test tubes
Dropper bottle of 0.1 M silver nitrate

 


Procedure


1.Place an ice cube into a petri dish and leave on your lab bench.  Record observations about any changes that occur to it during the lab.
 
2.  Light the candle and allow it to burn while you continue with the rest of the investigation. Record your observations of the burning candle in the space provided in Observations.

3. Tear the piece of paper into small pieces and place them on the watch glass. Place the watch glass and pieces of paper on the insulating pad. Light the pieces of paper with a match and allow them to burn completely. Record your observations of the burning paper.

4. Add a small scoop of table salt to a test tube that has been half-filled with tap water. Place your thumb over the top of the test tube and shake to dissolve the salt. Record your observations. Using the dropper, add 5 drops of silver nitrate to the salt water. Record your observations.

5. Place a small piece of magnesium ribbon in a test tube. Add 5 drops of hydrochloric acid to the test tube. Touch the bottom of the test tube with your fingertips. Record your observations.

 


Observations


1. What did you observe as the candle burned?  What was left after the candle burned?

2. What did you observe as the paper burned?   What was left after the paper burned?

3. What did you observe when you added the salt to the water in the test tube and shook it?  What did you observe when the silver nitrate was added to the salt water?

4. What did you observe when the hydrochloric acid was added to the magnesium metal?

 


Conclusions


1. Identify each of the following as either a physical change or chemical change. Give a reason for your answer.

a. Melting candle wax

b. Burning a candle

c. Tearing paper

d. Burning paper

e. Dissolving table salt

f. Mixing salt water and silver nitrate

g. Cutting a piece of magnesium ribbon

h. Adding hydrochloric acid to magnesium metal

2. Describe two observations you might make when a physical change occurs.

3. Describe two observations you might make when a chemical change occurs.

 


Critical Thinking and Application


1. How could you show that dissolving the salt in water resulted in a physical change?

2. How could you show that adding acid to the magnesium ribbon resulted in a chemical change?

3. The following changes can sometimes indicate that a chemical change has occurred. Explain how each change might result from a physical, not a chemical, change.

a. Change of color

b. Loss of mass

c. The substance seems to "disappear."