Add 1 mL of deionized water to the small test tube containing the precipitate and mix it and centrifuge it for 60 seconds. Then, add the supernatant into the boiling test tube and repeat this step one more time with another 1 mL of deionized water. Acquire a pair of metal test tube holders and heat the boiling test tube to evaporate the water for 15 minutes. Let is cool after and weigh it. Then, calculate a percent yield of zinc iodide and write a balanced chemical equation and determine the limiting
Experiment 2 Time | Observations | 5 minutes | Bubbled like sugar | Once salt water was added | Turned soapy white and thick | Equation: METHOD 1) Put 2 cm3 of castor oil into a 250 cm3 beaker and add 10 cm3 of 5mol.dm-3 sodium hydroxide from a measuring cylinder. (Take care when measuring this out and adding it to the beaker to avoid any drips and spills.) 2) Heat the mixture gently over a tripod and gauze, STIRRING CONSTANTLY with a glass rod (otherwise the mixture erupts). Allow to simmer (boil gently) for 5 minutes. Steady the beaker using
Obtain a clean-dry test tube. Place 0.3g of the unknown substance in the test tube. Next, add 10mL of distilled water to the test tube. Mix with a stirring rod until unknown is dissolved. 2.
Do an initial Benedict's test on the 15% glucose/1% starch and the beaker solutions for glucose by putting some of the solution and a roughly equal amount of blue Benedict's solution in a test tube, placing the test tube in boiling water for 90 seconds, and observing whether or not the solution changes color from blue. 3. Form a bag out of dialysis tubing by tying off one end, putting in enough 15% glucose/1% starch solution to fill it halfway, and tying off the other end leaving the other half of the bag void of anything (even air). Write down the solution's color. 4.
Once the procedure was performed three times, the collected iron fillings mass was obtained by using the digital weighing scale. After removing the iron fillings, the sand was removed next by using the property of sand that the sand was completely insoluble in the water. The iron free solids mixture was dissolved in 15.00 mille liters of distal water and heated by using stove top in a beaker. The solution was mixed for a while the benzoic acid and salt were allowed to dissolve completely and solubility was enhanced by heating the solution. The solution was decanted into another beaker.
First I made a water bath by filling the 100 mL beaker with cool tap water. I then placed crushed ice in the 100 mL beaker so the water level was just below the top of the beaker. I sprinkled a little salt in the ice water and mixed it well. I then filled the test tube half full with distilled water and set the test tube in the 24 well plate. I inserted the digital thermometer into the test tube and took reading every 30 seconds until the readings remained constant.
Lab Report: Crystallization of phthalic acid from water (microscale) Abstract The 0.60 g of phthalic acid is put in a water solution, which is brought to a boil to dissolve the acid into water. After the solution was clear with just the rock visible the test tube solution is now cooled in ice and stirred till crystals appear. Excess water is then removed, then the adding of ethanol is done to separate the water from the crystals. Tube is then placed in a beaker of hot water which aids in the removal of the solvent. After drying the compound the percent recovery was found to be 70%.
5a. Place a small amount (the size of an aspirin tablet) of copper II sulfate pentahydrate in a clean dry test tube and record your observations. Using your test tube holder, tilt the test tube and gently heat the contents for 4-5 minutes, while recording your observations. Make sure to observe the upper end of the test tube while heating. Allow the test tube to cool and record your observations.
To the second, add 10% NaOH dropwise until the pH is 14. (To do this, add a couple of drops of NaOH to the tube; stir thoroughly with a stirring rod; then touch the stirring rod to a piece of pH paper to check your pH.) To the third, add 0.5% sodium bicarbonate solution to pH 9, and to the fourth, add 2% HCl to pH 2. Record your observations on the data sheet. Repeat the above tests using 2% casein solution.
Procedure 1. Begin to prepare an EDTA solution. Weigh out 3.62-3.64 g of NaH2EDTA and record exact mass. Add the weighed amount to a 250 ml volumetric funnel carefully using a funnel Wash the funnel with water to ensure all of the solid is delivered to the flask Add 100-200 ml of water and mix. Enough water should be added so that the flask is full to the 250 ml mark Tightly wrap the top of the flask with a Parafilm when finished 2.