Determination of the molar mass of magnesium Aim To determine the molar mass of magnesium with the ideal gas equations and Dalton’s law about partial pressures. Materials and chemicals gas measuring tube 50.0cm3 graduated cylinder 1000.0 cm graduated cylinder 10.0cm3 cork with a hole copper wire thermometer barometer magnesium ribbon HCL 35% (concentrated) Background theory Dalton’s Law of Partial states that the total pressure of a gas is equal to the sum of pressure of each individual gas at a specific temperature. The combination of all the partial pressures of the gases that make up the atmosphere gives the total pressure of the atmosphere. The average pressure of the atmosphere is 101 kilopascal(KPa). Most of the pressure of …show more content…
This weight was recorded to four significant figures. After this, piece of magnesium was wrapped around the tip of copper wire. Following this, the buret was filled with about 10.0 mL of concentrated HCL and water was added until the buret was full. The copper wire with the magnesium was then putted into the buret and held in place with the rubber-stopper to make sure the copper wire wouldn't fall to the bottom. Distilled water was pure into the rubber-stopper to make sure the buret was completely filled and to make sure there wouldn't be any bubble. Then the buret was quickly inverted and pressed into a beaker with full of water. Finally after the water cooled down, the water level of the buret was measured inside beaker. This process was repeated for two more …show more content…
This experiment was to weigh the magnesium then wrap it with copper and to put it in a beaker with full of water in order to get the hydrogen gas. In the first trial the reaction happened real quick, this could be due to over using magnesium and it could have been improved by using less magnesium. But the rest two trials, they were pretty much ok. The figure shows that, ratio between H2 and Mg is 1:1 which means that there are equal molecules in both of them. Since the answer has to be four significant figure, the average molar mass of magnesium is 23.85
Next, we determined the mass of the penny by placing it on a balance. The mass of the penny was 2.47 grams. Afterwards, we placed the penny in a beaker filled with 20 mL of 6 M HCl. In the end we put the beaker in the fume hood and allowed it to sit overnight. During day two of the penny lab, we removed the penny skin from the beaker using tweezers.
After the water temperature began to stabilize, the highest constant temperature was recorded. This data was used to calculate the calorimeter constant. This enter procedure was repeated to calculate another calorimeter constant in order to find the average of both answers. After that value was calculated, a 600 mL beaker was filled with 300 mL of water and heated till it started boiling. An unknown metal located on the instructor's bench was obtained and the mass was calculated.
The hypothesis made, the density calculated in the experiment will stay the same because the density of the unidentified object will never change, was supported. The results support the hypothesis because in every trial the density always came out to 9g/mL. In trial one the mass was 71.16g, the volume was 8mL, and the density was 8.895g/mL, but when rounded to the proper sig fig came out to 9g/mL. In trial two the mass was 71.12g, the volume was 8mL, and the density was 8.89g/mL, but when rounded to the proper sig fig came out to 9g/mL. In trial three the mass was 71.14g, the volume was 8mL, and the density was 8.8925g/mL, but when rounded to the proper sig fig came out to 9g/mL. When averaged the mass was 71.14g, the volume was 8mL, and the density was 9g/mL. Errors that could have occurred are, not calculating the density correctly, not completely submerging the unidentified object with water in the graduated cylinder to get the volume, not rounding the sig figs correctly when finding the density, not measuring the unidentified object’s mass in grams, not measuring the unidentified object’s volume in milliliters, and not writing the correct units with the proper number or not the correct unit at all.
After seemingly all of the aluminum chloride has been funneled from the copper, one should take the filter paper out of the funnel and let it dry. One needs to let the filter paper dry before weighing it to see how much copper was produced in order to allow the water to evaporate. If one were to weigh the funnel paper while it was wet, they would not get an accurate measurement of how much copper was produced because the scale would show a reading of the amount of copper as well as the amount of water on the filter paper. Once the filter paper has fully dried, one can then weigh the paper in order to determine how much copper was produced. In order to do this one should take a scale and obtain a clean piece of filter paper along with the one with the copper on it.
Which of the following unit is used to indicate mass? a. Cm3 b. Um c. Mg d. mL 21. Which of the following demonstrate a chemical reaction of water?
Using the equation m = ΔTf/Kf , the molality of the unknown solution was found. Then, moles of unknown were calculated, which was used to calculate the average molar mass of unknown. Theory: After the experiment was completed, the data
The water percent is determined to be 42.06%. To find a percent error, a theoretical percent water must be used. To find the theoretical percent error divide the mass of water by the mass of magnesium sulfate heptahydrate and multiply by 100 to get a percent. The theoretical percent water is
I. Purpose: To experimentally determine the mass and the mole content of a measured sample. II. Materials: The materials used in this experiment a 50-mL beaker, 12 samples, a balance and paper towels. III.
Weighed 1 gram of NaC2H3O2 and mixed it with ionized water. Boiled 12 mL of 1.0M Acetic Acid added into a beaker containing the sodium carbonate on a hot plate until all the liquid is evaporated
Next, a 100 mL graduated cylinder was used to measure 60 mL of distilled water. The water was added to the compound and stirred with a glass-stirring rod until dissolved. Next, The flame test required the solution made during the solubility test. The experiment needed a metal wire that was dipped into the solution
But the difference was no bigger than 0.08, and after the values were rounded the same empirical formula was deduced. So the experiment can be concluded as successful. Evaluation: The method used was simple and easy to follow; however, it did not include how much oxygen was needed to react completely. Also it didn 't mention what magnesium oxide looked like after it finished reacting, so it was a guesswork of determining whether the reaction was finished or not.
Materials 1 calibrated thermometer, 1 scale that reads mass, 2 Styrofoam cups, 1 small lead sinker, boiling water in a beaker, 1 pair of kitchen tongs, 1 small cooking pot, stove top, distilled water, and 1 pair of safety goggles (I did not use a cork stopper). III. Procedure First, the beaker
Acids are proton donors in chemical reactions which increase the number of hydrogen ions in a solution while bases are proton acceptors in reactions which reduce the number of hydrogen ions in a solution. Therefore, an acidic solution has more hydrogen ions than a basic solution; and basic solution has more hydroxide ions than an acidic solution. Acid substances taste sour. They have a pH lower than 7 and turns blue litmus paper into red. Meanwhile, bases are slippery and taste bitter.
Introduction Buffer is a solution that resists a change in pH when bases or acid are added. Solutions that are acidic contain high concentrations of hydrogen ions (H+) and have pH values less than seven. Buffer usually consist of a weak acid, and its conjugate base or a weak base and its conjugate acid. The function of buffer is to resist the changes in hydrogen ion concentration as a result of internal and environmental factor. This buffer experiment is important so that we relies the important of buffer in our life.
That caused a new initial reading of NaOH on the burette (see Table1 & 2). The drops were caused because the burette was not tightened enough at the bottom to avoid it from being hard to release the basic solution for titrating the acid. The volume of the acid used for each titration was 25ml. The volume of the solution was then calculated by subtracting the initial volume from the final volume. We then calculated the average volume at each temperature.