Calculate the molarity of the original vinegar solution and its concentration in gdm-3, given that it reacts with NaOH in a 1:1 ratio. 7. 2.5 g of a sample of ethanedioic acid, H2C2O4.nH2O, was dissolved in water and the solution made up to 250 cm3. This solution was placed in a burette and 15.8 cm3 were required to neutralise 25 cm3 of 0.1 moldm-3 NaOH. Given that ethanedioic acid reacts with NaOH
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.
Calculate the volume of 0.250 M H2SO4 that contains 0.250 g H2SO4. 0.250 g H2SO4 x 1 mole x 1 L = 0.0102 L 98.12 g 0.250 mole 5. 1.50 g of NaCl is dissolved in 100.0 mL of water. Calculate the concentration. 6.
Put aspirin powder in a beaker and pipette exactly 30 cm3 of a 1 M NaOH solution onto the powder. Stir the beaker in order to dissolve aspirin completely. 3. Add 3 drops of phenolphthalein to the beaker with aspirin powder and NaOH solution. NaOH solution would be in excess and thus prepare 1 M of HNO3 solution in burette, which will be used in back-titration.
5. Potassium hydroxide solution: Use 0.01 M potassium hydroxide, 0.56 g/L. 6. Ammonium hydroxide solution: Add water to 10 mL of concentrated ammonium hydroxide solution to make 82 mL of a stock solution. Use 10 mL of the stock and dilute to 1 L with distilled water.
Percent H2O in Hydrate is equal 0.34/2.33=14.6% 3. The general formula of barium chloride hydrate is BaClg-nHZO, where n is the number of water molecules. Calculate the theoretical percent water for each value of n—divide the sum of the atomic masses due to the water molecules by the sum of all the atomic masses in the hydrate, and multiply the result by 100. Complete the table. | BaCl2 | BaCl2•H2O | BaCl2•2H2O | BaCl•3H2O | Sum of atomic masses (BaCl2) | 208.23 | 208.23 | 208.23 | 208.23 | Sum of atomic masses (nH2O) | 0 | 18.02 | 36.04 | 54.06 | Sum of atomic masses (hydrate) | 208.23 | 226.25 | 244.27 | 262.29 | Percent water in hydrate (theoretical) | 0% | 7.96% | 14.75% | 20.61% | In this lab we used a Balance, centigram
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.
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.
To perform this experiment, we will utilize emission spectra, titrations, and thermal gravimetric analysis, using knowledge from Experiments 10, 4, Titrations of Na2CO3 and NAHCO3 by HCl (hydrochloric acid) will be performed to determine the concentration of HCl, as well as the number of moles of HCl present within the sample of baking soda. As a result, we will be able to determine the molar concentration of HCl by determining its equivalence point (the point on the graph where the exact amount of rectant needed to perform a reaction has been added) from graphical analysis. Na2CO3(aq.) + HCl(aq.) ==> NaHCO3(aq.)
Empirical formula: CH5N Steps for molecular formula: 1- Calculate the molar mass of the empirical formula. 2- Divide the known (given) molar mass by the calculated empirical formula molar mass to get a whole number 3- Multiply that whole number through subscripts of the empirical formula to obtain the molecular formula. Example CH5N 12.01 g C x 1 C= 12.01 g/mol 1.008 g H x 5 H = 5.040