A2 Chemistry Coursework Section 1 Aims: I aim to find out the order of reaction with respect to [H2O2] and [2I-]. I aim to find out the activation enthalpy of the reaction by finding the rate of reaction at different temperatures using the Arrhenius Equation. The experiment will go as follows: Into a conical flask put 15cm3 of distilled water and add 2cm3 of [X]moldm-3 potassium iodide (KI) solution and 1cm3 of 2moldm-3 sulphuric acid. Then add to this 2.5cm3 of 5vol (0.42moldm-3) hydrogen peroxide (H2O2). For the second part of my investigation, the KI solution will remain a constant 0.3moldm-3 and the H2O2 solution will vary. H2O2 + 2I- + 2H+ -> 2H2O + I2 Methods to find the rate: 1 - Use a colorimeter to monitor the change …show more content…
Transmittance can be expressed as the ratio of the intensity of the transmitted light (It) and the initial intensity of the light beam (Io), as expressed by the formula: reference 4 T = It /Io Experimental Methods: Making up the solutions: The potassium iodide solution will be made up by first calculating the amount (in moles) of KI needed from the equation: concentration = amount/volume as I know the desired concentration(s) and how large a volume I want to make up. Then I can calculate how exactly how much solid KI (in grams) is needed for that concentration by using the equation: amount = mass/Mr - given the Mr of KI is 166.0028. Then to actually make up the solution, I will first brush the balance, place a plastic weighing container on it, and then tare the balance. I will then proceed to accurately weigh out the required mass of KI with a clean spatula. The hydrogen peroxide solution will be diluted from 20vol to [X]vol by using 20/[X] the volume of 20vol H2O2 in distilled water. Methods: Potassium iodide solution: 1. Using the equations; amount = mass/Mr and concentration = amount/volume, I calculated the correct mass of KI needed to make up the required concentrations of KI solution (0.05 through to 0.3moldm-3). I used the complete values throughout all the equations, and then rounded my final volume to an appropriate decimal place relative to the precision of the scientific balance I will use to make up the solution. 2. Solid KI (mass m) was weighed
First I will set up the apparatus as show above. I will add 1.5 grams
Purpose: Weighing objects. Figuring out the density with an object by calculated volume and Archimedes’ Principle.
Abstract: This two part experiment is designed to determine the rate law of the following reaction, 2I-(aq) + H2O2(aq) + 2H+I2(aq) + 2H2O(L), and to then determine if a change in temperature has an effect on that rate of this reaction. It was found that the reaction rate=k[I-]^1[H2O2+]^1, and the experimental activation energy is 60.62 KJ/mol.
Enter the precise mass in GRAMS of the potassium iodate used to prepare your primary standard solution.
mL cylinder to the beaker on the stir plate and empty it into the beaker. Place the pH probe in the beaker and record the pH in the data table. Drag the beaker to the red disposal bucket. Double-click the bottle of NaHCO3 to move it to the Stockroom counter. Repeat steps 5 and 6 for KNO3.
A 300.0-mL saturated solution of copper(II) peroidate (Cu(IO4)2) contains 0.38 grams of dissolved salt. Determine the Ksp.
1.2 1.0 0.8 0.6 0.4 0.2 0.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Concentration (mM) y = 0.1897x R2 = 0.99
4. Take a piece of dialysis(as cut earlier), find the mass of the dialysis, and the zero out the scale on
This experiment will measure the rate of oxidation of iodide ions by persulphate ions to derive the rate law for the reaction. Starch will be added to the reaction to facilitate the measure of time during the reaction. The reactant solutions will contain (NH4)2SO4 and KI, represented as:
3) Calculate the activation energy of the reaction using different versions of the Arrhenius equation.
concentration, record the absorbance readings at a fixed wavelength, and plot the absorbance vs. concentration data. The wavelength of 520 nm was selected for experiment Part
Purpose: To measure the heats of reaction for three related exothermic reactions and to verify Hess’s Law of Heat Summation.
2cm of a solution was tested and added 2 cm of 10% of potassium hydroxide solution and the test tube was shaked.
8. 1 g of solid KI (record the exact mass) and 3 drops of ammonium
3. Place about 3g of the mixture into the evaporating dish and carefully weigh it to the nearest 0.01g with the top loading scale and record its mass on the data sheet.