Lab Report On Magnesium Oxide

2. Obtained a 2-3 cm strip of magnesium metal ribbon and coiled it loosely into a small ball. Added the magnesium metal to the acid in the test tube.

During the immersion of the magnesium metal in the hydrochloric acid solution, white bubbles could be seen escaping the surface of the metal as gas was produced during the reaction. Depending on the temperature of the hydrochloric acid and the overall molar concentration, the rate of reaction differed but the same signs were shown. During the reaction between the magnesium metal and higher concentrations of hydrochloric acid, it was observed that the test tube grew quite warm to the touch. As the immersed magnesium strip sank down, it appeared coated in a layer of white bubbles that fizzed like a carbonated drink. In the lower concentrations of hydrochloric acid, the strip spent some time floating at the surface of the solution in the test tube, later sinking down to the bottom as the

) Suppose that some magnesium oxide smoke had escaped during the investigation, the Mg:O ratio would have increased from 58% to 72%. The final mass of MgO would have decreased because the magnesium oxide smoke is part of the product and when some of it escapes, it decreases the final mass.

Hypothesis/Prediction: The percent composition by mass of magnesium in magnesium oxide will not change significantly with each group that conducted the experiment. The composition of each substance should stay the same and any differences must be due to some error.

The first experiment is about the combustion of magnesium after which the ash is formed.

Based on my and other classmates' observations and results it can be proved that every time magnesium combines with oxygen to form Magnesium oxide the percent composition for magnesium will be 60.31% and for oxygen it will be 30.69 % (the results achieved by experiments are

    In this lab, a calorimeter was used to find the enthalpy of reaction for two reactions, the first was between magnesium and 1 molar hydrochloric acid, and the second was between magnesium oxide and 1 molar hydrochloric acid. After the enthalpy for both of these were found, Hess’ law was used to find the molar enthalpy of combustion of magnesium, using the enthalpies for the two previous reactions and the enthalpy of formation for water. The enthalpy of reaction for the magnesium + hydrochloric acid reaction was found to be -812.76 kJ. The enthalpy of reaction for the magnesium oxide + hydrochloric acid reaction was found to be -111.06 kJ. These two enthalpies and the enthalpy of formation for water were manipulated and added together using Hess’s law to get the molar enthalpy of combustion of magnesium. It was found that the molar enthalpy of combustion of magnesium was -987.5 kJ/mol. The accepted enthalpy was -601.6 kJ/mol, which means that there is a percent difference of 64%. This percent difference is very high which indicates that this type of experiment is very inefficient for finding the molar enthalpy of combustion of magnesium. Most likely, a there are many errors in this simple calorimeter experiment that make it inefficient for finding the molar enthalpy of combustion of magnesium.

About 80 mL of HCl was obtained and mixed with phenolphthalein. Using a LabQuest unit and Gas Pressure Sensor kit, the HCl mixture was added to the flask with the magnesium ribbon and allowed to react. When reaction was complete, the change of temperature and gas was recorded. This procedure was repeated for different masses of magnesium ribbon (masses found on page 89 of the lab manual). After the completed procedure, moles of H₂ produced in each trial were calculated. (The actual procedure can be found on pages 87-89 of the lab manual)

Using elemental analysis to determine the percent mass composition of each element in a compound is the first step in creating an empirical formula. There are many different types of elemental analysis, but in this experiment gravitational analysis and Beer’s Law are used. Elemental analysis is first used to find the moles of each element, then converted to mass, and then the percent mass of the element in the product is found (2).

| After ignition of magnesium light and toxic fumes are made, and white powder (2MgO or Magnesium Oxide) is left over.

In the experiment the magnesium reacts with the hydrochloric acid to create magnesium chloride and hydrogen. The balanced formula for this is:

The goal of this experiment was to determine the empirical formula for a hydrate of magnesium sulfate and water. The technique that was used was measure the mass of the hydrate and then apply heat to evaporate the water. Then determine the mass of water that was in the hydrate and the mass of the remaining magnesium sulfate. The equation for the hydrate is determined by calculating the mole to mole ratio of the water and the anhydrous. The resulting formula will be formated as: MgSO4*_H2O

It is expected that the concentration of hydrochloric acid will increase the rate of the reaction between magnesium ribbon and hydrochloric acid. By increasing the concentration of

How empirical formula of Magnesium Oxide is obtained by heating Magnesium in the presence of air?

5.3 mL of bromobenzne and 15 mL of anhydrous ether was then placed into the separatory funnel and was shaken and vented in order to mix the solution. Half of the bromobenzene solution was added first into the round bottom flask and as soon as a color change was observed, the remaining half of the bromobenzene was added drop wise into the round bottom flask. The mixture was then refluxed on a heating mantle for 10 minutes until most of the magnesium has been consumed.