The samples don’t have to have the same mass as long as it’s between 0.3 and 0.4g. Add about 20mL of water and 3 drops of phenolphthalein indicator to each sample and allow the solid to dissolve. Prepare a 50mL buret for use by washing it, rinsing it with tap water, and rinsing it twice with distilled water. Finally rinse it twice with 5mL portions of your sodium hydroxide solution. Mount the buret on the ringstand and fill it above the zero mark with the prepared sodium hydroxide solution.
Next, obtain a 5 mL serological pipet and thoroughly rinse it with the buffer solution, then discard the buffer solution into the 250 mL beaker. Now, use the pipet to distribute 5 mL of the buffer solution into three 50 mL beakers. Be sure that the 50 mL beakers have been cleaned are dried prior to this. Next, locate the three pre filled burets in the lab room. Find the buret labeled 1.0M HCl and add exactly 1.00 mL of HCl to just one of the three 50 mL beakers with buffer solution already in them.
9) The number of moles of H2CO3 in the reaction NaHCO3 + C2H4O2 NaC2H3O2 + H2CO3 is also the number of moles of NaHCO3. 10) Calculate the number of grams of sodium bicarbonate by multiplying the number of moles of sodium bicarbonate by its molar mass. OBSERVATIONS BEFORE REACTION Total Mass: 165.93 g Total Mass: 165.93 g Mass: Alka Seltzer Tablet: 3.82 g Beaker + Vinegar: 162.11 g Temperature: 20.9 °C DURING REACTION Observations: Alka Seltzer is fizzing and dissolving into the vinegar Gas is being released as bubbles form; it’s carbon dioxide Looks like a nice glass of frothy beer AFTER REACTION Observations:
Because this reaction is reversible, a fractional distillation is necessary to produce cyclohexene, water, and some impurities and a simple distillation is followed to further purify the product. [pic] (Fig. 1- Cyclohexanol dehydrated by sulfuric acid to produce cyclohexene) Procedure: 1. Mix five mL of Cyclohexanol and 2.5 mL of 9M sulfuric acid in a 25 mL flask. 2.
Place a funnel on the top of the buret and slowly add 5g of dry alumina. When all of the alumina has been added, rinse the inside of the buret with additional petroleum ether to flush down any alumina that may be stuck to the sides. Add another 1-cm layer of dry clean sand on top of the alumina. Drain the solvent from the column until the solvent is at a level just above the top of the sand. The column is now ready for the addition of the mixture to be separated.
| Experiment #3Weight of Zinc: 2.0 gramsWeight of Iodine: 1.1 gramsExperiment #6Weight of Zinc: 2.02 gramsWeight of Iodine: 2.5 grams | 3. Then add 5 mL of acetic acid (acidified water) into the “R” boiling tube, and then after you pour it swirl vigorously. Continue swirling until the tube turns back into room temperature. Then you have to decant the solution in boiling tube “R” into boiling tube “P” without any granular zinc leaving boiling tube “R”. Then wash the zinc in the boiling tube “R” by adding 5 mL of acidified water, swirling and then decanting the solution into the “p” boiling tube.
| Experiment #3Weight of Zinc: 2.0 gramsWeight of Iodine: 1.1 gramsExperiment #6Weight of Zinc: 2.02 gramsWeight of Iodine: 2.5 grams | 3. Then add 5 mL of acetic acid (acidified water) into the “R” boiling tube, and then after you pour it swirl vigorously. Continue swirling until the tube turns back into room temperature. Then you have to decant the solution in boiling tube “R” into boiling tube “P” without any granular zinc leaving boiling tube “R”. Then wash the zinc in the boiling tube “R” by adding 5 mL of acidified water, swirling and then decanting the solution into the “p” boiling tube.
There are several different ways to create baking soda, but the Athenium Baking Soda Company chose to make baking soda by reacting ammonium hydrogen carbonate with a highly concentrated aqueous solution of NaCl or brine. An equation to demonstrate this process is: NH4HCO3(S) + NaCl (aq) → NaHCO3 (aq) +NH4Cl(aq) This salt-water concentration not only contains a high concentration of sodium chloride, but also concentrations of calcium chloride, potassium chloride, and lithium chloride. Because of this fact residue of NH4HCO3 will possibly contain CaCl2, KCl, and LiCl. These contaminants of the brine will provide flaws to the baking soda, and thus production must be checked often by chemists who analyze the baking soda for lifespan, composition, purity, and quality. There are a couple different ways to determine the percent composition of baking soda.
A sample of the baking soda will be heated until it decomposes to leave solid sodium carbonate according to the following equation: 2NaHCO3(s) --> Na2CO3(s) + CO2(g) + H2O(g) Eq. 2 The calculated percent by mass of the sodium bicarbonate should be 100% or nearly 100% if it is pure; if the percent by mass significantly deviates from this percentage, then further experimentation is needed to determine what other substances are present in the sample. The second experimental procedure to determine the purity of the baking soda sample is a titration of a baking soda solution and
6. Combine the iron and copper (II) sulfate together into the distilled water. Heat to a slow boil for 10 minutes. 7. Remove from the heat and allow to cool until you can hold it.