Lesson 3.2 Making Dirty Water Clear

You may take clean drinking water for granted-just turn the tap and you get clean water ready to drink.  Did you know that most drinking water starts off as river water, which is often quite dirty?  In this investigation, you will mimic the first step in converting dirty water to clear water. 

Read the investigation on page 51 in your textbook.  Now, perform the investigation and complete the lab report.  If you are working at home, you will have to make some modifications to the investigation as follows.

Apparatus:   
·    Use an ice cream or yogurt container to catch the filtered water.
·    Use a strainer or some other device to hold the filter.
·    Use an ordinary watch or clock that has a second hand.

Lab Report

Title:

Problem:

Diagram:

Procedure:

Observations:

Conclusion:

 

Question 1. How would you redesign the filter so that it would produce clearer water?

Question 2. How would you redesign the filter so that it would produce clear water faster?

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Lab Report

Title: Making Dirty Water Clear

Problem: To design and make a filter from the materials to make dirty water clear.

Diagram: Your diagram should be similar to this one.

Procedure:

Step 1: Design and construct a filter using the listed apparatus and materials.

Step 2: Pour the dirty water into the filter and time how long it takes for the water to pass through the filter.

Step 3: Look at the filtered water and record observations.

Observations: Depending on how well you constructed your filter, the water may be clear or it may still have visible dirt in it.

Conclusion:   If your water came out clear, you can conclude it is possible to filter dirty water using the materials in this investigation.  If your water came out dirty, you can conclude it is not possible to filter dirty water using the materials in this investigation.  

 

Question 1. How would you redesign the filter so that it would produce clearer water?

You would have to use finer cloth and sand to produce clearer water.

Question 2. How would you redesign the filter so that it would produce clear water faster?

You could make the filter larger (more surface area).  You could also try to prevent the filter from clogging by pre-filtering out some of the larger particles or letting some of the dirt settle first to produce clear water faster.


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