Separating Mixtures Project

Unit Project

Documenting the Scientific Method
Separating Mixtures Project

Separating Mixtures: How can you separate salt water to make pure and drinkable fresh water?

Design and build a device to separate a mixture of salt water into its components. For example, what device could you build to get the most drinkable water from salt water if you were on a stranded island in the middle of the ocean? Gather data on the amount of water collected and the purity of the water, which can be done through taste tests. Change one variable at a time as you alter your device to obtain more water or more pure water.

Step 1: Observe/question • Question: How can you separate salt water to make pure and drinkable fresh water?
• Research: A minimum of 1 page typed in an outline format. You must include at least 5 resources in the proper bibliography format (2 of the 5 sources must be a book/encyclopedia/scientific magazine). • Any words included in your outline that a typical 8th grade student would not understand MUST BE DEFINED and EXPLAINED within the outline! • Research topics: o Types of mixtures o Salt water’s chemical make-up.
o Methods of separating mixtures. o Pros & Cons of each method of separating mixtures.

Step 2: Hypothesis • Sketch a design for your separating mixtures device. Label each part of your device with the object name and briefly describe what is occurring at that point. This part of your project does not have to be typed, but remember to write legible! • Write a short paragraph answering the following question: what part of your research led you to this hypothesis? (Make sure to explain WHY you chose this as your hypothesis.)

Step 3: Experiment • TAKE PICTURES OR VIDEO DURING YOUR EXPERIMENT PROCESS. THIS IS A REQUIRED PORTION OF YOUR WRITE-UP! THE PICTURES/VIDEO WILL ALSO BE GREAT FOR YOUR PRESENTATION! • You will need to collect a lot of information in this experiment. Put this data into TWO separate charts. See back for more information. • In your write-up, make a list of materials, a step-by-step procedure used to build your device (read over your procedure to make sure it makes sense!) and TWO charts (see back). • Build your device. Continue to test throughout your process and make changes as needed. DON’T FORGET TO RECORD YOUR DATA THROUGHOUT THE ENTIRE
PROCESS!!! o Don’t forget to change one variable at a time!!! o Data Table 1: Qualitative observations chart includes: • Trial number (alter your device by ONE variable to try to get more drinkable water or more pure water) • What changes did you make • Why did you make those changes • How did this affect the device? o Data table 2: Quantitative observations chart includes: • Trial number • Amount of salt you started with – don’t forget units! • Amount of water you started with – don’t forget units! • Taste before (perhaps you can use a scale of 1-5, but be sure you include a description of what a 1 represents vs. a 5) • Taste tests can be performed by you and/or another friend/family member. • Amount of drinkable water produced – don’t forget units! • Taste of your final result. • Taste tests should be performed by same people as before

Step 4: Evaluate • Type a couple paragraphs that answer the questions below by evaluating your hypothesis and experiment. Don’t forget to include specific details from your experiment data when writing your evaluation. o Does your data support your hypothesis? How does your final result compare to your initial sketch? Did you have to make many changes? Why or why not? Provide a final sketch of your BEST design/trial. Why do you think this device worked “better” than the others? o Which variables couldn’t you control? How could that have affected your experiment results? o What did you learn/find out from this experiment? o What would you do differently/change if you would do this all over again? (Note: Do not simply say that you would change your hypothesis to be correct. Instead, think about the process. What could you do differently to make it more effective? What could you do to improve this project if you did it again?)

Step 5: Communicate • Remember, this is a BRIEF summary of your project (2-3 minutes)! • Your presentation should follow the scientific method. Explain what you have done for each step of the scientific method. • What is the answer to your question in step 1? What science supports this answer? Summarize your findings. • What did you learn? Please include specific details about your new knowledge. • How are you assessed? See the rubric below when planning your presentation:

• Organization & flow: _________/11 points o Short/Brief introduction & conclusion (1pt) ▪ Introduction - Specific description of why did you choose the project ▪ Conclusion – One thing for the audience to remember from your project o Describe each step in detail (includes specifics) ▪ Question & Observe (2 pts) ▪ Hypothesis (2 pts) ▪ Experiment (2 pts) ▪ Evaluation (2 pts) o Follows order of scientific method (1 point)

• Visual/Documentation: _________/4 points o Data table, pictures, displayed experiment, video, etc. (This could be the same as your product) (1 pt) o Make visual effective (appropriate time, size, description, best effort) (3 pts)

• Time: _________/1 points o 2-3 minutes

• Presentation skills: _________/3 points o Voice- sound excited, clear, loud, and not too fast (1 pts) o Eye contact with the audience (spoke to the audience, not to note cards/board) (1 pt) o Distracting actions- do not lean, rock back and forth, play with clothes and/or face, hair, etc. (1 pt)

• Professionalism: _________/2 points o Serious about presentation (1 pt) o Present like a scientist, to a scientist. (1 pt) o No gum! (-1 pt)