The temperature probe was used to stir the p-xylene and ensured an accurate reading. The temperature graph was saved for future reference. This procedure was repeated three times in total to account for any errors in measurement. Using the
2. Obtain a clean and dry crucible and lid. Crucibles very slowly adsorb small amounts of water vapour from the atmosphere and must be heated for a minute or two to get rid of adsorbed water molecules before you can get an accurate “initial mass” for a crucible. Crucibles are usually heated in clay triangles, which in turn are set on top of rings attached to ring stands. 3.
The color change in the copper sulfate when we heated it indicated that all of the water has evaporated, to be sure, we heated and weighed the crucible and CuSO4 again, and it came out to be .901g again. Finally, before disposing of the CuSO4 we added a little bit of water and observed the changes, the crucible quickly heated up and bonds were formed. Section 2: Results Measurement include: • The initial mass of crucible: 19.071g • The mass of the CuSO4: 1.509 • The mass of CuSO4 after mortar and pestle: 1.424g • The mass of the crucible and the CuSO4: 19.972g Observations: • The color change when the copper sulfate was heated,
Gently stir the pellets until the acid is dissolved by shaking the the apparatus. Lift the calorimeter lid and wash out its contents and the thermometer. Repeat this experiment using 50.0 mL of 1.0M acetic acid. Repeat experiment using 25.0 mL of each 2.0M sodium hydroxide and 2.0M acetic acid. Data Table(s): Reaction equation Mass of solid NaOH Initial Temp.
• After the flask was heated, I removed it from the heating mantel and allowed it to cool to room temperature. • Next, I poured 15mL of absolute ether and 9mL of bromobenzene into the 250mL flask and waited 5 minutes for any reaction. • There were no signs of reaction after 5 minutes; therefore the lab assistant used a glass stirring rod to crush the magnesium in order to get the reaction started. When this was done, the liquid became cloudy, rapidly bubbling, and the color turned rusty red. • Next, I added 25mL of absolute ether and attached a reflux condenser to the flask.
IV. Materials, Methods and Procedures: Materials: * Bunsen Burner * Ring and Ring Stand * Crucible tongs * Crucible and lid * Clay triangle * Scissors * Sandpaper * Magnesium ribbon * Weighing balance Methods and Procedures: 1. Fasten a ring to a ring stand and place a clay triangle in the ring. Place the crucible in the clay triangle and position the cover on the crucible such that a small gap is left open. Heat until the crucibles bottom is red hot.
I then allowed the remaining liquid to evaporate leaving behind salt. I poured the salt into the weighing dish and weighed the mass and calculated and recorded into table 1. Data Table 1: Experiment Data Grams Percent of Mixture Iron Fillings 0.9 gm 19.6 % Sand 1.4 gm 30.4 %
Doing the Experiment: 1.Heat the covered crucible for about 2 minutes. After the two minutes remove the burner and allow the crucible to cool. After allowing crucible to cool down (place fingers close to bottom of crucible bowl to make sure it has cooled down). It has cooled completely when you feel no heat. 2.When crucible is cool transfer it to the balance using tongs.
The normality of the unknown base is calculated after the solution has reached the end point. The amount of substance being delivered is calculated in units of equivalents per litre using the formula: VaNa = VbNb Experimental In order to titrate the acid with the unknown base, a solution of the acid was prepared. 5.1722 (±10%)g of potassium hydrogen phthalate acid is obtained using a weighing boat and transferred into a volumetric flask containing 250mL of boiled distilled water. Volumetric flask was shaken several times in order to assist the powder to dissolve. Once dissolved, 24.9734 (± 0.0045)mL of acid was pipetted into an Erlenmeyer flask along with 25mL of cool (recently boiled) distilled water.
We weighed the resulting powder to be 3.228 grams. We then transferred the powder nutmeg into a 50 ml round bottom flask and added 15 ml of dichloromethane. We placed our flask in to a standard heat reflux apparatus and gently refluxed the mixture. We waited until we saw the first drip of liquid in the apparatus and heated for 15 minutes. After the mixture was heated, there was solid on the bottom and liquid on the top of the flask.