The cylinder with the sebacoyl chloride was 27.14 grams and the cylinder with hexamethylenediamine was 36.14 grams. We then calculated the mass of the reactants, which is found when we found the difference of the weight of the cylinders before and after sebacoyl chloride and hexamethylenediamine were added. The total mass of the reactants was equal to 41.35 grams. After we calculated these results, we started to create the chemical reaction. We put the sebacoyl chloride and the hexamethylenediamine in separate beakers, but then slowly added the hexamethylenediamine to the beaker with the sebacoyl chloride in it.
Using the combined gas law, the calculated volume of the gas at STP would be 0.0377 liters. If one wanted to find the volume of mole this gas at STP, then all that is required is to divide the 0.0377 liters at STP by the original number of moles of magnesium from the start of the experiment; this would yield the results at STP if one mole of magnesium was reacted, which is the same as one mole of hydrogen produced according to the chemical equation. In the end, the volume of mole of the hydrogen gas produced in this experiment would be equal to 23.6
2. Explain how to determine the formula mass (mole mass) for a compound. Molar mass is the mass (in grams) of one mole of a substance. Using the atomic mass of an element and multiplying it by the conversion factor grams per mole (g/mol), you can calculate the molar mass of that element. First, find the chemical formula for the compound.
Objective The objective of the experiment was to measure and analyze the reaction rate of tert-butyl chloride with sodium hydroxide, and plot it in a graph in order to observe the rate. Procedure Part A- Measurement of the SN1 Reaction Rate of Tert-Butyl Chloride • 100 mL of a solution of propan-2-ol and water (1:1 ratio) were collected from a container provided by the instructor, and they were placed in a 250 mL Erlenmeyer flask, which was subsequently cork-stoppered. Afterwards, 150 mL of NaOH were acquired and placed in a beaker, and in turn this 150 mL sample of NaOH was used to fill a 50 mL buret to the highest mark, and this buret was attached to a butterfly clamp attached to a ring stand in preparation for a future step. In a 100 mL
Standard Preparation: 100 mg of standard ascorbic acid was weighed precisely and transferred to a 100 ml volumetric flask, added 70 ml of 0.5% sodium metabisulphite and dissolved by shaking. The volume was made up to the mark with 0.5% sodium metabisulphite for getting a concentration of 1 mg/ml. 2 ml of this solution was taken into another 100 ml volumetric flask and made the volume up to the mark with 0.5% sodium metabisulphite which resulted in concentration of 0.02 mg/ml. The solution was filtered through 0.45 µ nylon syringe filter. Sample Preparation: 2.5 g of sample was weighed accurately and transferred to a 100 ml volumetric flask.
Explain how the molarity of the standard solution (the alkali) was calculated in the experiment (equation explained)- 0.1M of NaOH is required, this equation will be used: Concentration = moles volume This will be rearranged to find the moles needed to carry out the experiment. The concentration of the experiment using NaOH is 0.1M so we just need to rearrange the equation to find the molarity. 0.1 x 0.250 = 0.0250 moles Number of moles = mass RFM 0.0250 = mass 40 0.0250 x 40 + 1g (mass) Explain how this enabled you to accurately calculate the molarity of each acid used in the titrations (equations explained)- Molarity of the acid = molarity of the alkali x volume of the alkali volume of acid Firstly we will need to add up all of the volumes found within the titration to find an average: 13.10+13.20+13.10= 13.13 Molarity of Ethanoic acid = 0.1 x 25.00 = 0.190 mol dm-3 13.13 Molarity of Hydrochloric acid = 1.0 x 25.00 = 0.077 mol dm-3 32.53
2. Experimental procedure 2.1. Chemicals and materials Melamine (99%), titanium dioxide with anatase (99.7%), isoniazid (ISN, >99%), isopropanol anhydrous (IPA, 99.5%), 1, 4-benzoquinone (BQ, ≥98%) and ammonium oxalate (AO, ≥99%) were purchased from Sigma Aldrich. The molecular structure and chemical properties of isoniazid are given in Table 1. Sodium hydroxide (NaOH, 99%) and methanol (MeOH, analysis grade) was purchased from Merck Millipore, Germany.
C is plotted and fitted to a logarithmic-line to illustrate the saturation effect, shown in Figure 1. Then using equation 12.8 in the lab manual, C/Y is calculated and plotted versus C and fitted to a straight line, shown in Figure 2. From the fitted line, Ymax, which is the maximum number of moles of acetic acid that can be adsorbed on the surface of the charcoal per gram of charcoal, can be calculated from the slope. Then, using Ymax and the value of the y-intercept, K, which is the ratio between the rate constant k1 of the forward reaction (adsorption on the charcoal) and the rate constant k-1 (detachment from the charcoal), can be determined. For calculations, refer to Appendix E. Finally, multiplying Ymax by Avagadro’s number will give the number of AA molecules adsorbed on the surface of one gram of charcoal at saturation.
It uses a balanced chemical equation, mole ratio, and sometimes needs mole mass. Molar mass is the mass in grams in one mole of substance. The units for molar mass are in grams per mole. Molar mass is the same number as the formula mass that needs to be found except it is converted. Formula mass is the mass in atomic mass unit of one particle of
The antioxidant activity of the extracts was measured on the basis of the scavenging activity of the stable DPPH free radical (as cited in Dong et al., 2014). Evaluation of antioxidant activity of astaxanthin through DPPH assay was modified according to the procedures reported by Lewis (2012). 12 mls of 0.1 mM DPPH solution with methanol was prepared. A measurement of 0.005 g of DPPH was added to 12 mls of methanol which was measured with a graduated cylinder into a small foil-wrapped flask. A number of 11 two ml microcentrifuge tubes were assembled and was labeled as: Tubes 1a-c through 3a-c: Product Extract Dilution 1 through 3 (repeat three times for 9 tubes), Tube 4: Positive control, α-tocopherol and Tube 5: Negative control, solvent only.
To find the number of moles of each reactant added, volume in liters was multiplied by the molarity (concentration). 2. The second step is about finding the theoretical yield, which will help to determine the correct amount of Ca(OH)2 can be made in chemical reaction. However, before doing this, it’s necessary to find whether CaCl2 or NaOH is a limiting reagent. For each test, the limiting reagent is found by multiplying the number of moles of the reactant by 1 mole of Ca(OH)2 and dividing then by a number of moles of reactant from the reaction.
32 100 μL of afore-prepared sample solution and the mixed reference standard were diluted 100 times with ethyl acetate. 50 μL of these dilution solutions were separated on the TLC plate coated with SNISG. The plate was developed with petroleum ether: ethyl acetate (4:1) and the movement of solvent was usually controlled at 1 cm from the upper edge. After completion, the plate was dried until no solvent smell remained. It was sprayed with an ethanol solution containing 10% sulfuric acid, and heated at an infra-red drier until obvious color came up, as shown in Fig.2 (B.ab).