Before beginning taking measurements, read through the instructions below and make a neat table in which to record all the numerical data. Using tongs put a clean crucible on the hotplate. Heat the crucible for approximately 5 minutes. Turn off the hotplate. Carefully remove the crucible to a piece of wire gauze and allow the crucible to cool for one minute. Transfer the crucible to a desiccator and allow to cool for approximately 5 minutes or until cooled to room temp. Weigh the crucible and record the mass to the nearest 0.001g from the balance. Repeat the heating and cooling process. Again weigh the crucible and record the mass to the nearest .001g. Add all of the sample material from the vial into the crucible and weigh the crucible and record the mass …show more content…
Summary of the procedure was that there were 4 mass measurements taken during the lab. And that the hotplate was used to heat both the crucible and the sample. Some sources of error could be that the sample and /or crucible where not on the hotplate long enough, an error in the measurement of mass and an error in the calculations also that the crucible with sample was removed from the hotplate before the sample turn all white. A major result is that after the water is removed from the sample it turns to one color but when a couple drops of water the sample changes back to a blue color like the sample was at the beginning. My results of the calculating the mass percent composition is relevant to the last goal, my observations is relevant to the second goal and the formula