10/5

          This week our labs were focused on density and how we can find other variables with it. Our first lab was where we tried to measure the density of gas. The first test run,  in order to find the mass of the CO2, we measured the mass of the glass jar, the sheet of glass, and the mass of the water after its displacement (after we measured the mass of the glass jar+sheet of glass+water+CO2 we emptied the water into a beaker, of which we previously had measured the mass, and found the mass of the water) We then took the total mass of the jar, the sheet, the CO2, and water and subtracted the mass of the jar, the sheets of glass, and water to get only the CO2........ we calculated a gain in mass... we were very confused.... and our second experiment proved the same......

        We also had a quiz where we had to calculate the thickness (h) of a thin sheet of aluminum foil and a thick sheet. We knew the density of aluminum is 2.7g/1cm3. In order to find the height we used the equation m/L*W*H=2.7g/cm3....... First we measured the length and width of the thick sheet of aluminum (L=19.2cm, W=9.8cm), then we found the mass (m=1.16g) then we inserted them into the equation          1.16g/(19.2cm*9.8cm)h=2.7g/cm3        we cross multiplied and divided and came up with h=.00228cm      

      Then we took the measurements of the thin sheet of aluminum foil..... L=18.60cm, W=13.90cm, m=0.7 and density=2.7g/cm3  We inserted this data into our equation 0.71g/(18.60cm*13.90cm)h=2.7g/1cm3 and after cross multiplying and dividing got h=.00102 (we only received an 18/20in this quiz due to our confusion with significant digits)

If one substance has a greater density than another substance and they are combined, the one with the GREATER DENSITY WILL SINK (water has a density of 1g/mL)