Percentage Composition by Mass of Magnesium Oxide Essay

Percentage composition by mass of atomic number 12 oxide Report Objective To measure and calculate the ratio of milligram to oxygen in magnesium oxide. To comp be the lab ratio to the percent composition calculation based on the formula. Hypothesis Based on the justness of definite proportions, the percentage composition of magnesium oxide should be around 60% magnesium and 40% oxygen.Materials* Goggles* Centigram or analytical balance* 2-4 cm magnesium ribbon* Steel Wool* Porcelain crucible and lid* Bunsen Burner* Retort Stand* Ring Stand and Clamp* Clay Triangle* Crucible tongs* Glass Stirring Rod * Distilled WaterCalculations + ObservationPlease see the back of the report.DiscussionB) The fact that magnesium oxide was formed, which is a new substance, proved that a chemical reaction had taken place. E) Yes, the law of definite proportions is valid, because most of the other groups that had not encountered as many an(prenominal) errors as us and they had more accurate results w hich were enveloping(prenominal) to the predicted compositions according to the law. The rest had similar results to us which proves that their errors were similar to ours. H) The white film on the surface of the magnesium was polished because it prevents reactions of magnesium and gas elements in the air. This was infallible because we wanted magnesium to react with oxygen and therefore had to remove the white film.ConclusionJ) Yes, the law of definite proportions is valid, because most of the other groups that had not encountered as many errors as us had more accurate results. The rest had similar results which proves that their errors were similar as well. Sources of errorYou have to be very precautious while doing this taste. Here are reasons/possible errors that could have been encountered * The magnesium oxide could have been lost through the crucible during the heating process. This could result in the loss of the product. To prevent this, the lid should be caboodle sligh tly off-center on the crucible so that only the air goes in.* When the glass inhalation rod was used to crush the magnesium, there is a mellowed chance that the magnesium oxide could have been left on it before adding the peeing, resulting in the loss of product. To prevent this, the stirring rod should be held above the crucible and then pour the water slowly on to the end of the stirring rod so that the water would run down into the crucible while dragging the MgO from the stirring rod. * Magnesium could have not reacted with oxygen completely. * The crucible might be left dirty with other particles in it that could have made variations in the MgO reaction.* The water could be contaminated.* All water might not have evaporated.* Magnesium having not been crushed completely into powder after reaction.* Rushing through experiment because of lack of time.* Chance of Problem with weighing scale.* Crucible had extra weight due to extra contents that were unseen.