Analysis/Conclusion:

The purpose of this lab was to determine if a reaction between an unknown metal and an acid can be used to identify the metal. During this lab, HCl was reacted with an unknown metal in a closed flask submerged in a water bath. The HCl then reacted with the unknown metal, producing hydrogen gas. The temperature, pressure, and volume were recorded during the reaction (as seen in graphs 2 and 3), allowing the number of mole of hydrogen gas to be calculated using the ideal gas law. Then using the calculated amount of hydrogen, the mass of the unknown metal sample, and the three stoichiometric possibilities, an approximate atomic weight was calculated. Possibility 1, with a ratio of 2:1 and an aaverage atomic weight of 12.94 g/mol, yielded the possibility of argon or carbon. But possibility 1 was quickly eliminated, because neither argon nor carbon are metals. Possibility 3, with a ratio of 2:3 and an aaverage atomic weight of 38.83 g/mol, produced the possibilities of chlorine or argon. Similarly, both possibilities were also eliminated due to the fact that neither are metals. Possibility 2, with a ratio of 1:1 and an aaverage atomic weight of 25.88 g/mol, yielded the possibilities of magnesium or aluminum. The unknown metal was then determined to be magnesium, because its atomic weight was closer to the value of 25.88 g/mol. This result was fairly accurate, for magnesium typically reacts quickly with magnesium producing hydrogen gas, as in this lab. 
 

Although the results of this lab were rather accurate, as in any lab, the possibility for error is inevitable. For example, since the reaction between magnesium and HCl occurs so quickly, the stopper needed to be inserted tightly and quickly in order to preserve the results. If the stopper was not inserted quickly enough, some of the hydrogen gas produced may have been released into the air, falsifying the data. Additionally, if the mass of the unknown metal was not recorded correctly, inaccurate data and conclusions may have been produced. In future labs, I would emphasize the importance of properly recording masses, and quickly inserting the stopper into the flask, in order to preserve data and ensure accurate results. I would also increase the number of trials for this lab, in order to achieve more plentiful and accurate data.