Physical & Chemical Porperties of two Metals Essay

Purpose The purpose of this lab is to examine the physical and chemical properties of Magnesium and Copper. Definitions: Chemical change: A chemical change is a kind of change in which a specific type of matter is converted to a new one. Physical change: Physical changes are those in which a change in the form, but not the composition of matter occurs. Physical property: Physical properties can be observed or measured without changing the composition of matter, they are generally used to observe and describe matter. Chemical property: Chemical properties can not be determined unless a substance undergoes a change in its composition. If you answer the question â€Å"Can I get the original substance back?† with no, then you are observing chemical properties. Physical and Chemical Properties of two Metals (Mg & Cu) † Data Collection Data Collection Observations for Magnesium: Process Observations a) Examine a piece of magnesium ribbon. Silver in color, shiny and smooth surface b) Attempt to bend a piece of magnesium ribbon. Breaks easily c) Obtain two 3 cm pieces of magnesium. Clean the surface of each with a piece of steel wool. Still silver in color, still shiny but became more smooth d) Place one of the pieces of magnesium ribbon from part c) into a test tube containing 3 mL of water. Add two drops of phenolphthalein solution and shake for 30 seconds. Liquid turned in a light pink e) Using crucible tongs, hold the other piece of magnesium ribbon in a burner flame to ignite the magnesium. Remove the burning magnesium from the flame and allow it to continue to burn. Save the ignition for part f) Got bright, then melted and turned white f) Place the ignition product from part e) into a test tube containing 3 mL of water. Add 2 drops of Phenolphtalein and shake for 30 seconds. Liquid turned in a light pink, ash is on the bottom of the test tube Add a 1 cm piece of magnesium ribbon to a test tube containing 1 mL of 2.0 mol/L HCL and observe for 30 seconds. got warm, liquid is bubbling (new gas created), the piece of magnesium ribbon turned white Add a 1 cm piece of magnesium ribbon to a test tube containing 1 mL of 2.0 mol/L nitric acid and observe for 5 minutes. Liquid is bubbling (new gas created), Liquid turned cloudy, got warm Physical and Chemical Properties of two Metals (Mg & Cu) † Data Collection Data Collection Observations for Copper: Process Observations a) Examine a piece of copper wire. Bronze in color, smooth and shiny surface b) Attempt to bend a piece of copper wire. Does not break easily c) Obtain two 3 cm pieces of copper wire. Clean the surface of each with a piece of steel wool. Bronze in color, shiny and very smooth d) Place one of the pieces of copper wire from part c) into a test tube containing 3 mL of water. Add two drops of phenolphthalein solution and shake for 30 seconds. Liquid turned cloudy/white e) Using crucible tongs, hold the other piece of copper wire in a burner flame to ignite the copper. Remove the burning copper from the flame and allow it to continue to burn. Save the ignition for part f) Got warm, color of liquid turned grey, copper wire bends easily f) Place the ignition product from part e) into a test tube containing 3 mL of water. Add 2 drops of Phenolphtalein and shake for 30 seconds. No changes observed Add a 1 cm piece of copper wire to a test tube containing 1 mL of 2.0 mol/L HCL and observe for 30 seconds. No changes observed Add a 1 cm piece of copper wire to a test tube containing 1 mL of 2.0 mol/L nitric acid and observe for 5 minutes. No changes observed Physical and Chemical Properties of two Metals (Mg & Cu) † Conclusion/ Evaluation Conclusion/Evaluation Conclusion In our experiments the magnesium seemed to have reacted better in our experiments than the copper, although some of their physical properties are the same, both are for example shiny in their color and have a smooth surface.. In three of our copper experiments no change took place whereas the magnesium always showed some kind of reaction to our experiment. But magnesium and copper do also seem to have some reactions in common, as to see at experiment D, where we took steel wool and cleaned the surface of the magnesium and copper, physical properties were observed, the surface of both got even more smooth and it got more shiny. We were observing a physical change in part C where the magnesium stripe broke easily, but the copper did not break easy at all. We were also observing chemical changes such as the boiling of the magnesium in experiment F, a new gas was created. Physical properties were observed in experiment E for the magnesium as well as the copper where the phenolphthalein and the water changed its color to pink with the magnesium and in a cloudy white with the copper stripe, meaning that magnesium, water and phenolphthalein or copper, water and phenolphthalein do change the color of the created. We did not observe any changes in experiments G,H and I for our copper stripes, whereas we observed changes in experiment H for the magnesium part where the liquid started bubbling, a new gas was thus created which is evidence for a chemical change. Evaluation This experiment showed very well how different copper and magnesium react by doing several similar experiments with each of them, but I think there is a lot of room for improvement because I am quite sure that there are either changes or specific properties occuring in parts G to I with the copper. The fact that no reaction took place might have been due to not enough liquid for those experiments, it might have been helpful to either add more or do several trails with each one having a different value of liquid in it. In general it is always better to have numerous trails, this would give us better evidence about changes which might not have been regular, but occured due to unpreciseness when doing the experiments. It might have also been interesting to measure the temperature of the boiling liquid, whether or not there is a difference between the reaction with copper and magnesium or not. We only had about 40 minutes to complete our entire experiment, which was, in my oppinion, not enough time to complete all steps properly with a high preciseness, more time would have been helpful, too.