Lab Conclusion on Density

Lab Conclusion on Density

In the lab of measuring density, precision and accuracy are very key components. Precision is the exactness of a measurement or good technique. Now accuracy is the value that we measured compared to the true value that the book has. Precision and accuracy are important because you need to have good technique and have your value close to the true value to minimize the error analysis. If you do these steps correctly you are a good chemist but if you do them poorly they could affect your whole experiment or lab. When we first saw about precision and accuracy in the dart example you can have poor precision and good accuracy and vice versa. Because the darts could be clumped together but not even close to the bulls eye and have good precision and poor accuracy but the measurements will be poor in the final run. So when they are together in the bulls eye then you have become a good chemist.
When doing the lab we were introduced to two ways of finding density, one commonly used in algebra, and the other not as common. The first step to find density is finding the volume by using (length x width x height). This way is the most used way to find volume because most kids are familiar with it. The other way is water displacement. If you have a beaker of water then you look at eye level to see what the initial volume is and then drop the substance in the water and then that gives you the final volume. Once you have that then you subtract the final by the initial to get the volume. I myself like water displacement because it is more interesting and I am not very good with algebra. Now after you have fond the density, you can identify it by its physical property. Physical property is a characteristic of a substance that does not involve a chemical change such as density color or hardness. For instance a aluminum cube can be described as: solid, sliver, cube, and hard.
To reduce your error analysis you must do a series of steps (if needed). First, you must tap out any bubbles that may be in the test tube for that could affect the value. Then get at eye level and place the substance in the water and read the numbers at eye level. When a substance floats then you must poke it down with your pencil tip because if you use the eraser then more weight would be added to the test.
Like the story of the gold necklace, you can find the density of everyday items to make sure they are real and not counterfeit. The density lab has provided me insight on many different equations, methods, and concepts for knowing the true meaning of density.