Calculate the concentration of grams of sodium stearate per milliliter of diluted solution. To do this, multiply the concentration of sodium stearate in the dishwashing liquid by the dilution of the solution (1.50 mL dishwashing liquid per 100 mL solution). Answer = 1.5 *10^-4 g/mL 4. Calculate the number of moles of sodium stearate in a single layer. To do this, first take the number of drops used to achieve the monolayer (1 drop) and convert it to mL using the calibrated number of drops per mL.
* 25 mL of distilled water was stirred in to form the calcium chloride solution. * Stoichiometry was used to determine how much Na2CO3 was needed for a full reaction. 1.0g CaCl2·2H2O(1mol CaCl2·2H2O/147g CaCl2·2H2O)(1mol Na2CO3/1mol CaCl2·2H2O)(106g Na2CO3/1mol Na2CO3)=0.72g Na2CO3 * The 0.7g of Na2CO3 was weighed and put in a small cup. * 25ml of distilled water was stirred in to make a sodium carbonate solution. * The sodium carbonate solution was poured into the beaker with the calcium chloride solution.
AP Chemistry P2 Experiment 2: Formula of a Hydrate 9/24/2013 Purpose: Calculate the percent composition of water in a hydrate and determine the empirical formula of the hydrate. Procedure: 1) Set up ring stand with ring clamp, clay triangle, crucible with lid, and burner. Adjust the height of the ring stand. 2) Dehydrating Procedures: 3. Measure approximately 1 g of Copper(II) Sulfate Hydrate into the crucible and crucible and lid.
The molar mass of a compound or atom is the mass of 1 mole of anything; this is relative to the atomic mass from the periodic table. The percentage yield from an experiment would be the actual yield divided by the theoretical yield multiplied by 100. We need to know how to balance chemical equations due to law of conservation of mass. Being able to turn moles into mass and mass into moles through the equation “m=nM” rearranged to find out other components. We need to be able to find the limiting reagent and be able to go through the process of gravimetric stoichiometry.
Pre-Lab Questions 1. A determination of the molar mass of methyl alcohol (CH3OH) yielded the following data. Temperature of boiling water bath 99.5o C Barometric pressure 738 mm Hg Temperature of room temperature water 24.0o C Density of room temperature water 0.9973 g/mL Trial 1 Mass of empty pipette 1.557g Mass of piet and condensed methyl alcohol 1.571g Mass of pipet and water 16.001g Mass of condensed methyl alcohol 0.014g Mass of water in filled pipet 14.444g Volume of pipet 14.483mL Molar mass of methyl alcohol (experimental) 28.69 g/mol Molar mass of methyl alcohol (theoretical) 32.05 g/mol Using the data, fill in the rest of the table. The volume of the pipet is equal to the volume of water inside the pipet. Use the relationship of mass and density to determine this volume.
The Ksp for the experiment was found to be an average of 4.29x10-5, which means that 4.29x10-5 parts of a mole of solid are dissolved in the solution. 2. Fill in the data table below paying careful attention to correct units and correct number of significant figures. Data and Results Table |Unknown number |40375 | |Molarity of HCl (from bottle) |0.1843M | | |Trial
Use the balance to weigh the empty beaker, and record. 2. Measure 50 ml sea water using a graduated cylinder, then pour into beaker 3. Determine the weight of the beaker plus the sea water. Record the combined weight 4.
Using 1 ml micropipette add 1.0 MR in each four 10 ml volumetric flasks. 3. Prepare following MR solution in four flasks: flask 1: add 5 mL pH 4 buffer (graduated cylinder) and fill to the mark with water flask 2: add 5 mL pH 5 buffer and fill to the mark with water flask 3: add 5 mL pH 7 buffer and fill to the mark with water flask 4: add 1 mL 0.01M NaOH and fill to the mark with water. 4. Record the spectrum for these four solutions in range 400-700 nm.
Add 0.5 ml concentrated HCl and 1.0 ml 15% KI solution. Mixed exactly 1 minute and leave for 5 minutes in a dark place. Add 0.5 ml starch solution, 20 ml distilled water. Mix and titrate with sodium thiosufate solution. Calculate the exact normality of Na2S2O3 knowing that in this chemical reaction 1 gram-equivalent of K2Cr2O7 react with 1 gram-equivalent of Na2S2O3 (1 mole K2Cr2O7 react with 6 moles Na2S2O3).
Gravimetric Determination of Sulfate Purpose The purpose of this lab is to determine the percentage of sulfate in the hydrate by precipitating the sulfate as barium sulfate. Materials Filler paper Sodium sulfate Graduated cylinder Bunsen burner Watch glass Beakers (250 mL, 400 mL) Rubber bulb Graduated pipette Beaker tongs Funnel Filter Paper Sodium Sulfate Drying oven Wash bottle Stirring rod Silver nitrate Hydrochloric acid Distilled water Small test tube Procedures First, .4861 grams of sodium sulfate was placed into a clean 400mL beaker. Exactly 200mL of water and 1mL of HCl was added to the same beaker. A watch glass was placed on the beaker and the solution was heated using the Bunsen burner to a gentle boil. The watch glass was removed with the beaker tongs.