(4 points) q = m × c × Δt Given: q=? m = 34.720g c = 4.18 j/(g x °C) Δt = 41.6°C - 25.2°C = 16.4°C q = (34.720g) (4.18 j/(g x °C) (16.4°C) q = 2380.13j You are trying to figure out the energy change of the water which is the surroundings in the lab. To do that you must take the mass of the metal, which for me was Aluminum, and multiply it by the heat capacity of the water, which was given, then multiply that by the change in temperature, which is the final temperature of the mixture
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.
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 an Irregular Shaped Solid 1) Obtain a sample of metal and determine the mass. 2) Fill a 100 mL or 50 mL graduated cylinder with water, recording its volume. 3) Using the water displacement method, determine the volume of the object. 4) Determine the density and percent error. Part D: Density of Methanol 1) Find the mass of an empty 10 mL graduated cylinder, and then fill approximately 9 mL of methanol and record volume.
Pb (NO3) 2 10. A compound is 42.3 % C, 5.94 % H, 32.9 % N, and 18.8 % O and has a molecular mass of 425.25 g/mol. Calculate the empirical and molecular formula. C15H25N10O5 11. How many moles of Al2O3 are produced by the reaction 200. g Al?
Conclusion 10 Grams of Potassium chlorate when decomposed produces 3.915576 grams oxygen gas and 6.083363 grams potassium chloride Atomic Weight of Magnesium Introduction In this lab we will determine the atomic weight of magnesium by measuring the amount of hydrogen gas evolved when hydrochloric acid reacts with magnesium. The reaction is as follows: Mg + 2HCl -> H2 + Mg2+ (aq) + 2Cl- (aq) There is a one to one relationship between the number of moles of hydrogen gas evolved and the
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.
In order to find which reactant is the limiting reactant, an equation based on the molarity of the Copper (II) Chloride may be used, or the products of the reaction may be observed. If the bluish tint of the Copper (II) Chloride fades, or disappears before the Aluminum is completely used to form Aluminum Chloride, then it can be said that the Copper (II) Chloride is the limiting reactant in this reaction. On the other hand, if all of the 1.5 grams of Aluminum pebbles are used to create Aluminum Chloride before the Copper (II) Chloride solution changes color, then it can be said that the Aluminum is the limiting reactant in this reaction. Hypothesis: If 1.5 grams of Aluminum pebbles are placed in 100 ml of 0.25 molarity Copper (II) Chloride aqueous solution in order to determine which of the reactants is the limiting factor, then the Copper (II)
We found the mass of our pure alcohol to be 10.23g. The volume of our pure alcohol was 10.97mL. With these numbers, we used the formula mass/volume to find the density of our pure alcohol to be .9325g/mL. The percent error of our experiment was found to be 18.19% with an absolute error of .1435%. Conclusion:The purpose of this lab is to prepare and purify a fuel, ethanol C2H5OH.
Single Replacement Reaction Laboratory Modified from Glencoe Chemistry - Matter and Change, Glencoe McGraw-Hill, 2002 Objectives Observe a single replacement reaction Measure the masses of iron and copper Determine the mole ratios and the limiting reactant Chemicals Iron filings (Fe) – 20 mesh Copper(II) sulfate pentahydrate, (CuSO4·5H2O) Distilled water Materials Stir rod 100-mL beaker 250-mL beaker 25-mL graduated cylinder Weigh paper Balance Hot plate Beaker tongs Wire mesh insulated pad screen Distilled water wash bottles |Lab Data - Reaction of Copper(II) Sulfate and Iron | | Mass of empty 100-mL beaker |(g) | | | Mass of 100-mL beaker