Lab for Chemistry
Discussion The purpose of the Density Lab was to determine the identity of four unknown solids and two unknown liquids by calculating their densities and comparing them to a density chart, taking into account error analysis and finally classifying the substances. In order to calculate this density, we first found the mass of the container that was to be holding the substances. We then found the volume of the substance, and lastly determined the mass of the container and substance. We subtracted (Container + Substance) – Container to find the mass of simply the substance. In order to distinguish density, we took the final mass divided by the volume, and identified the substances based on Density Charts we found online. Originally we hypothesized that we would be able to identify these substances based on the densities we calculated, yet this proved to be harder than it seemed, however our hypothesis was correct. We now could concluded the densities and identification. The density of Unknown Liquid 1 was 1.26 which was found to be Colorless Glycerin (also density of 1.26) and Unknown Liquid 2 was 0.88 or Rubbing Alcohol (colorless). Unknown Solid 1 has a density of 7.20 or Iron, Solid 2 is 2.59 and Aluminum, Solid 3 is 5.47 and Tin, while Solid 4 has a density of 9.81and Nickel? We
Errors Analysis (Distinguishes percent of error in calculations)
Some errors we faced were water being displaced when pouring the metals into the test tubes (could have changed volume). Also, we should have given the scale more time to get and exact answer rather than writing down one of the first numbers we saw. Now, there are ways we can certainly improve this experiment. One would be to take more time to get and exact volume rather than generalizing based on previous data (30.0 exactly for all initial volumes of water). We realized that this could have thrown off our calculations for final density and thus our identification. The analytical balance should be used in
Errors Analysis (Distinguishes percent of error in calculations)
Some errors we faced were water being displaced when pouring the metals into the test tubes (could have changed volume). Also, we should have given the scale more time to get and exact answer rather than writing down one of the first numbers we saw. Now, there are ways we can certainly improve this experiment. One would be to take more time to get and exact volume rather than generalizing based on previous data (30.0 exactly for all initial volumes of water). We realized that this could have thrown off our calculations for final density and thus our identification. The analytical balance should be used in