In the first part, five 100 mL flasks of 5 mL ligand solution, 5 mL 2 M sodium acetate, 4 mL 3 M NH2OH, and 1-5 mL Fe2+ solution are diluted with water. The absorption spectrum for varying concentrations of Fe2+ are measured using a spectrophotometer and the data is graphed in Excel. The slope of the line is ε in the Beer-Lambart equation A = εcl. In the second part of the experiment, eleven flasks containing diluted stock solutions of Fe2+ and ligand are mixed with 5 mL 2 M sodium acetate and 4 mL 3 M NH2OH and diluted with water. The absorption spectrum is measured using a spectrophotometer and the data is graphed in Excel.
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
The purpose of the experiment was to do a solution, which molarity is 0.20 mol/l, from water and an ionic compound. Our ionic compound was zinc sulfate (ZnSO4). Our task was to make one hundred milliliters (100 ml) of the solution. Materials To execute the experiment we used the following equipment: - a beaker - a volumetric flask - a plastic spoon - a scale - a pipette - a funnel - a cork cap We also used solid zinc sulfate (ZnSO4), and distilled and deionized water to make the solution. Calculations To figure out the amount of zinc sulfate that we had to add to the water, so that the molarity of the solution would be 0.20 g/mol, we did the following steps: First we calculated the amount of the zinc sulfate to add in moles.
Cylinder was rinsed with distilled water. * * 2. 2.0 ppm standard: 2.00 mL of 10.0 ppm phosphate solution was placed in a 25 mL graduated cylinder and diluted to exactly the 10 mL mark with distilled water then poured into a plastic cup labeled 2. Cylinder was rinsed with distilled water. * 3.
Part C: Density of Sodium Chloride (NaCl) Solution, a sample of NaCl was obtained and measured using a 100mL beaker and a 10mL pipet to determine the concentration of the solution. In order to obtain the appropriate result, a calibration graph and density measurement was used to determine the concentration of the sodium chloride solution. In conclusion, based on the water temperature of 21.8°C in part A’s graduated cylinder experiment obtained, it was determined that the average density was .0973g/mL with a percentage error of 2.5%. When graphed the measurement was equal to Y=0.988x. Part B: The graduated pipet’s average density at 22.3 °C was determined to be 0.9785g/mL with a percentage error of 1.89% shows the graduated pipet to be more accurate and precise.
Zing Substances. For ionizing substances, such as NaCl , 1mosm is 1mmole times the number of ions formed when each molecule dissociates. One mmole of NaCl is 58 mg, but when it dissociates, it yields 1 mmole of Na+ (23mg) and 1mmole of Cl ( 35mg). Therefore , 58 mg of NaCl is 2 mOsm of NaCl is put into a beaker and distilled water added to make 1 liter, the osmolarity is 2mOsm/l. A) How many mosm solute will 1 gram of NaCl yield?
Experimental First, we weighed 2 samples, each has 1 gram of NaHCO3-KCl mixture Second, we put the samples in 2 crucibles (A and B) and weighed them. (crucible + sample; WA1 and WB1) Third, we heated both samples on a hot plate for 30 minutes. Fourth, we weighed the samples again (crucible + sample; WA2 and WB2) Lastly, we determined NaHCU3 percentage in the mixture using the following method: WA1 – WA2 x 100% 0.309 WA1 – WA2 x 100% 0.309 * * Results * Theorectically: * Discussion When sodium hydrogen carbonate is heated, new products are formed; sodium carbonate, water vapor, and carbon dioxide gas. This reaction may be presented in a different form with a measure of molecules: @Na2CO3 + H2O + CO2 (solid) (solid) (gas) (gas). Once the reaction of sodium hydrogen carbonate takes place, carbon dioxide gas is released, as well as water vapor.
A cuvette block, four cuvettes, three 50 mL beakers, one 150 mL beaker, and one 5mL pipet were obtained. The phosphate buffers NaH₂PO₄ and Na₂HPO₄ were procured weighing .4060g and .4106g respectively. The phosphate buffers were then transported to the 150mL beaker. Next 50mL of distilled water was measured using a graduated cylinder and added to the 150mL beaker. Twenty drops of bromothymol blue was also added to the 150mL beaker.
Mix. k. Measure out 3/4 cup of the solution from cup 3 and add it to cup 4. Mix. l. What are the relative salt concentrations of cups 1–4? Example: Cup 2 is made up of half stock solution and half tap water, which is a 50 percent relative salt concentration.
Approximately 20 drops of a .04% Bromothymol blue solution was then added to the beaker of the phosphate buffer. Using a clean 5 mL serological pipette, transfer 5 mL of the phosphate buffer and Bromothymol blue solution to each of three clean 150 mL beakers. Next, using the buret for HCl, add 1 mL of HCl to one of the three beakers, then label this beaker “Yellow”. Next use the buret for NaOH and add 1 mL of NaOH to another of the three beakers, and label this beaker “Blue”. Lastly add 1 mL of water using the buret for water to the last beaker, and label this beaker “Green”.