At the second titration, the experiment was exactly the same as the first titration but the H2SO4 solution was used to instead of the HCl solution. The same step as the first experiment was repeated. In the third experiment, the buret had used Ba (OH) 2 thoroughly rinsed three times. 10mL of HCl
In each trial, the initial reading, final reading and the volume of HCl used was recorded down as quantitative results. The average volume of hydrochloric acid was found to be 12.03mL. The amount of sodium carbonate in the 10.00ml of solution was found to b 0.05 mol. The amount of hydrogen chloride that was dissolved in the average volume of acid is 0.365g. Through these calculations, the concentration of hydrochloric acid was found to be 8.3 mol•L-1.
* Trial 1 36-25.5=10g * Trial 2 36-25=11g * Trial 3 35.5-25=10g 2. Calculate the density of the unknown liquid for each trial. (Divide the mass of the liquid calculated above by the volume of the liquid.) * Trial 1: 10.5/50=0.20g/mL * Trial 2: 11/49=0.20 g/mL
Calculate the percent error in the molar mass value. Enter both values in the Data Table. Molar Mass Na2CO3 = 105.99 g/mol – this is the closest molar mass to what I calculated, so the unknown M2CO3 must be sodium carbonate. Percent Error: 93.08g/mol – 105.99 g/mol (100) = 12.18% error 105.99 g/mol DISCUSSION Review the procedure and list the possible sources of error that would cause either the molar mass of the unknown to be (a) too high or (b) too low. The goal of this lab was to discover the unknown group 1 metal (M) of the compound M2CO3 by dissolving the compound in water and adding a solution of calcium chloride, CaCl2 to the solution in order to precipitate the carbonate ions to reveal the molar mass of the unknown element, thus determining the identity of the unknown element.
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
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). Determination of peroxide value. Weigh 3.00 g oil (with precision of 0.001 g) into a 250 ml Erlenmeyer flask. Add 10 ml chloroform and swirl to dissolve oil. Add 15 ml acetic acid,
Simply, the law states that matter cannot be created or destroyed only changed in form. The purpose of this lab is to attempt to verify and observe the law of conservation of mass. In any chemical reaction, the total mass of the reactants is always equal to the mass of the products. In this lab it is stated that safety goggles are required and worn, also a lab apron. Balance 1 balloon Weighing paper 125 ml flask 50 ml graduated cylinder 5g baking soda 15ml vinegar First the mass of the empty flask and balloon is recorded.
AP* Chemistry Solubility Equilibrium SOLUBILITY EQUILIBRIA (The Solubiliy-Product Constant, Ksp) We’ve got good news and we’ve got bad news… The good news: Solubility equilibrium is really simple. The bad news: You know all those solubility rules that state a substance is insoluble? They are actually a bit soluble after all. Only the future attorneys among you read the fine print. Soluble is often defined as greater than 3 grams dissolving in 100 mL of water.
The purpose of this lab was to perform a titration on 10.000 mL of sodium hydroxide solution with 0.10 mol/L sulfuric acid solution. In this lab we performed numerous trials to find the amount of sulfuric acid solution that would neutralize 10.0 mL of sodium hydroxide solution and averaged the trials to find the amount; this data could then be used to find the concentration of the sodium hydroxide solution through solution stoichiometry. To do this we used a burette with the capacity of 50.00 mL with an uncertainty of 0.04 mL, a pipette of 10.000 mL with an uncertainty of 0.015 mL, a clamp stand, a titration flask(an Erlenmeyer flask) and bromothymol blue indicator. The apparatus was set up like so; 0.00mL (graduation at top) Burette contains 0.10M H2SO4(aq) 50.00mL (graduation at bottom) Erlenmeyer flask contains 10.000mL of NaOH (aq) as well as bromothymol blue indicator (10.000mL was measured with a pipette) Evidence Table 1: Raw Data collected from the Titration Lab showing the initial and final burette readings of the titrant of 0.10M ± 0.005M H2SO4(aq) Qualitative Observations Before any sulfuric acid was added, the solution was colourless and clear. After adding three drops of brymothymol blue indicator, the solution was now a clear blue colour.
So, those carbonyl group could be aliphatic or part of the aromatic ring because they share carbonyl group. In the reaction with 2,4 Dinitrophenylhydrazine, all of the 5 test tubes had positive results, both aldehyde and ketone had positive results, all of the test tubes had precipitates. During the Tollen’s Test, the aldehydes was oxidized and reduced silver ion to silver metal . So, the positive test results was aldehydes. In the Fehling’s test, only the aliphatic aldehyde had positive results which showed the red precipitate.In the Iodoform test, only methyl ketones had the yellow precipitates.The last time is Chromic Acid Test, only aldehydes could oxidized by chromic acid, and changed to green color.