1 x pipe clay triangle 1 x electric scale
1 x ruler 1 x tongs.
Method:- A
A clean 10cm strip of coiled magnesium ribbon was placed into a pre-weighed crucible with lid and reweighed and the mass recorded. The crucible as then placed on the clay triangle and strongly heated, (periodically removing the lid to allow oxygen into the crucible) until the magnesium was completely burned. Finally the crucible was allowed to cool and again weighed and the mass recorded.
Observations:- A
After a short period of time being heated, the lid of the crucible was lifted and a small amount of smoke appeared. Inside the crucible there appeared to be an orange glow. After finally leaving until no metallic coil remained, small amount of greyish resin remained inside the crucible.
Results:-A
Evaluation:- A
The results for this experiment were not as expected. The actual simplest form of magnesium oxide is MgO There are a few reasons why the results of this experiment show a 25 % error and different results than originally anticipated. As the crucible lid was lifted too much of the smoke within the crucible may have escaped, thus the amount of magnesium/ oxygen bond would have been lowered. In addition there may not have been enough oxygen entering the crucible, which would have led to a lower magnesium/oxygen bond to occur.
Experiment B:
Materials & Apparatus:- B
7-8 cm strip of magnesium ribbon quickfit conical flask
20 cm3 hydrochloric acid, (diluted acid which is 2.00moldm-3)
bung tubing
clamp stand
gas syringe electric scales
ruler strip of sand paper
Method:- B
An 8cm strip of magnesium cleaned, using a strip of sand paper, coiled, and then weighed and the mass was recorded. 20 cm3 of hydrochloric acid poured into a small quickfit conical flask and then bunged. Next the starting reading on the gas syringe was recorded. The bung was then removed and the magnesium dropped into the acid and the bung immediately replaced. Once the reaction was allowed to complete the final reading of the gas syringe was recorded.
Observations:- B
On immediate contact with the liquid, the metallic coil bubbled rapidly and released what appeared to be a white vapour. As the vapour rose into the gas syringe, volume increased. This reaction took approximately 2 minutes to complete until there was nothing of the metallic coil remaining.
Results:-B
Ionic Charges:
magnesium Mg 2+
hydrogen H 2+
cloride Cl -
Evaluation:- B
This experiment was very successful, as the 1: 1 ratio shows a correct figure. However, there of course is room for error, as there appeared to be 2% error in the calculations. The reason this may have occurred could be, as there was an immediate reaction once the magnesium was dropped in the hydrochloric acid, the bung may not have been replaced quick enough, thus any smoke created that the onset of the experiment may have escape.
