Cool the filtrate to room temperature, add 1.5 g of sodium nitrite, and stir until reaction is complete. 5. Pour this mixture, while stirring, into a beaker containing 25 mL of ice water to which 5 mL of concentrated hydrochloric acid have been added. The diazonium salt of sulfanilic acid should soon separate as a finely divided white precipitate. Keep this suspension cooled in an ice bath until it is to be used.
After completion of the solubility tests, the appropriate solvent, cyclohexane, was selected for large-scale recrystallization. The unknown was weighed for the large-scale recrystallization then the same process was repeated to test the solubility. The solute dissolved after adding of about 60 mL of solvent, it was set aside to cool to induce crystal reformation. The solution was then seeded and set alone once more. When the process was complete, the crystals
On a glass slide, 1 drop of distilled water was placed. Then, a loop-full of culture was transferred on the slide and it must be spread. It is then allowed to dry. Then, the smear must be heat fixed by exposing it to flame for few times until it got fixed. It is to prevent the cell from washing away during the staining and washing process.
After cooling, the flask was weighed in an analytical balance. The experimental molar mass was 45.56g, which is closely identical to the 46.068g of the molar mass of ethanol. The percent error between the two values is 1.10%, the probable sources of error are the following: the size of the tiny hole in the aluminum foil, measurement of the temperature in the thermometer, and measurement of the initial volume of the flask. The recommendation for the experiment is to dry the flask completely before measuring the initial mass and to closely observe if the temperature of the water bath is
Use a stopwatch to track the time of the combustion of ethanol. While the water within the beaker is being heated, use a stirring rod to stir it. Put the fire out when 4 minutes have elapsed. For safety precautions, let it cool off a bit before using the scale to measure and record, the final mass of the alcohol burner containing the ethanol. Subtract the mass of the alcohol burner gained in step 4 to achieve the final mass of the alcohol.
The Effect of Alkaseltzer Tablets on the Boiling Point of Water Zackary Zambrano Chemistry Honors Mrs.Gregor Period-3 10/5/16 Introduction Statement of Purpose: The purpose of this experiment is to see whether or not alkaseltzer tablets have an effect on the boiling point of 100 mL of water. The control is just water, the variable groups are 100 mL of water with one tablet, and 100 mL of water with two tablets. “What exactly is boiling? The technical definition is what occurs when the vapor pressure of a liquid is greater than or equal to the atmospheric pressure.”(Lopez,k) Simply put water, boils when enough energy is released to cause bubbles and then turn to vapor. When water begins to boil, the water will continue to boil at
Decomposition of Aspirin Studied with UV/Visible Absorption Spectroscopy Aims: To determine the concentration of salicylic acid, formed from the hydrolysis of Aspirin, at regular intervals using the UV/Visible Absorption Spectroscopy From the concentration of salicylic acid, concentration of Aspirin to be determined using an equation Calculate the rate constant of this reaction and its order from a plot of graph of ln(aspirin) vs time Discuss the overall flaws and improvements to the experiment Results: As per schedule1, 0.212g of aspirin was added to 50 ml boiling water to form salicylic acid in a 100 ml flask, of which 1 ml was then pipetted to a 50 ml volumetric flask at the 5th min. Following an ice bath, the solution was mixed
Place the thermometer through the lid and record the temperature of the water, Tinitial. 7. Add the NaCl powder into the Styrofoam cup by removing the lid and quickly start the stopwatch. Place the lid back on the Styrofoam cup. 8.
One solution is to keep the volume of the water consistent. For example, if the water volume is decided to stay constant as 1000mL for every trial, one can always first fill the tub with 400mL of tap water and then add ice or hot water to manipulate the temperature. In addition, the process can be facilitated by marking 1000mL on the plastic tub since the same tub will be used throughout the
Absolute zero is when temperature is 0 K, leading to pressure and volume to also equal zero. The calculated number is slightly off from the actual, accepted value for absolute