While we've figured out ways to represent why items like the chocolate chips, sand, and black pepper were removed from the water with tools like the colander, strainer, and coffee filter, we're not really sure where the salt, sugar, citric acid and vinegar went.
We're planning possible investigations to conduct to help us figure out if these substances are still in the water, and here's what the two classes came up with:
We're planning possible investigations to conduct to help us figure out if these substances are still in the water, and here's what the two classes came up with:
Here are our tests:
| 1. The Microscope Test: We'll look at a sample of our dirty water under the microscope. We'll also put salt, sugar, vinegar, and citric acid in their own water samples and look at them under the microscope, too. We'll see if we can identify anything in the dirty water we've still got and compare it to what we find individually. Comparing them will see if we can actually identify anything in our water sample. We realize we may not be able to tell anything a part from one another. Looking at each ingredient under the microscope will help us understand the size of each when it comes in contact with water. |
2. The Taste Test: We will NOT drink the dirty water we made, but we will test sugar, salt, citric acid (we discovered this is ok to consume by reading the bag's label), and vinegar both outside and mixed with water. If we can still taste the substance when it's mixed with water, then we will have some evidence that some of it is still there. | |
| 3. The Weight Test: We'll get four cups of water and weigh them. And we'll get a sample of the four ingredients we don't know of their whereabouts. We'll weigh those individually, too. We will put each ingredient in a cup of water and then weigh it together. If the weight of the water increases by the weight of the ingredient added, then that will be evidence that it's in there. |
4. The Water Level/Stirring Test: We'll draw a line that indicates the top of water in a cup before we add an ingredient to it. We'll stir the water and see what happens to the ingredient in the water and also what happens to the water compared to the line we drew. | |