a) Write the equation for the reaction. b) Calculate the number of moles of Fe2+ present in 1.0 dm3 of the solution. c) Calculate the molar mass of hydrate iron(II) sulphate. Hence calculate the value of x. 4.
A. metallic B. covalent (polar) C. ionic D. covalent (non-polar) 9. The number of moles of ions in 1 mol of copper(II)phosphate is A. 1 B. 2 C. 4 D. 5
A mixture of Br-, Cl- and PO43- ions was subjected to an anionic column packed with polym-N(CH3)3+OH-, eluted with 9mM sodium carbonate. (i) Arrange the above analyte ions in order of increasing retention time in the anionic column. (3 marks) (ii) Describe how the analyte ions were separated in the anionic column according to order of retention time answered in part (2)(i). (8 marks) 3. An unknown compound is irradiated with an excitation photon.
Repeat the titration until there are two titres within 0.1cm3 of each other. Record results in a suitable table. Results: Rough Titre: 7.653 First Run: 6.553 Second Run: 6.453 Third Run: 6.553 Calculations: During the titration, iron(II) ions are oxidised to iron(III) ions and manganate(VII) ions are reduced to manganese(II) ions. The equation is as follows: 5Fe2+(aq) + MnO4-(aq) + 8H+(aq) ? 5Fe3+(aq) + Mn2+(aq) + 4H2O(l) The above equation shows that one mole of manganate(VII) ions reacts with 5 moles of iron(II) ions in acid solution.
Where it resulted to values of 3.990602 x 10-3 s-1, 4.653278 x 10-3 s-1, 5.944044 x 10-3 s-1, 7.499958 x 10-3 s-1, 7.499958 x 10-3 s-1, 9.84554 x 10-3 s-1, for flasks 4, 5, 6, 7, 8. Then the Ionic strength was calculated using the equation µ=½∑ ci zi2 . Which resulted in 4.5392142 x 10-2, 6.4999998 x 10-2, 1.23823528 x 10-1, 2.21862742 x 10-1, and 4.17941175 x 10-1. It
Date : 18/02/2013 Micro-scale Determination of the Activation Energy of the Hydrogen Peroxide-Iodide Reaction Abstract: The purpose of this experiment was to determine the rate at which hydrogen peroxide decomposes to water and oxygen with the use of an iodide catalyst. Using the logarithmic form of the Arrhenius equation: ln k’ = -Ea/RT + ln A . the activation energy was determined to be 52.3 kJ/mol. It was also found that increasing the temperature also increased the rate, as there was more energy available to increase the speed of the reaction. Introduction: The purpose of this experiment was to determine the Activation Energy of the Hydrogen Peroxide-Iodide reaction.
The orders of the reaction were 2(n=m=1), k was 0.004174 L mol-1s-1 and the activation energy was 82.577kJ/mol. Introduction: Determination of orders and rate constant The reaction studied is iodide-persulfate reaction, of which the equation is showed below. 2I- + S2O82- I2 + 2SO42- The rate constant (k), and orders (n and m) of the reaction with respect to each of the reactants, in the expression for the rate of reaction R are showed below, R = k [I-]n[S2O82-]m where the square brackets indicate concentrations expressed as moles per liter. In order to determine their values, two sets of experiments need to be carried out. In the first set (part A(i)), the initial rate of reaction will be measured for different reaction mixtures in which the S2O82- concentration is held constant but the concentration of I- is varied.
0.15 M NaCl solution = 0.15 moles of Na+ atoms + 0.15 moles of Cl- atoms = 0.30 Osmoles In other words, the solution is said to have an osmolarity of 0.30 Osm (or 300 mOsm) Assume the osmolarity of the ICF of body cells to be 0.300 Osm (300 mOsm) 2nd, determine if the solute is a PENETRATING particle or is NON-PENETRATING. 3rd, determine whether a concentration gradient of NON-PENETRATING particles exist or not. If a gradient exists, determine where the higher concentration of non-penetrating particles exist; in the ICF or the ECF? (Assume the 300 mOsm concentration of particles in the ICF of body cells is composed of non-penetrating particles) 4th, repeat your definition of osmosis in order to determine if water will move: a. into the cell b. out of the cell c. not move into or out of the cell Osmosis is the diffusion of water across a membrane from a region of lower concentration of non-penetrating particles into a region of higher concentration of non-penetrating
Preliminary work backs up this hypothesis. Because, when doing the practical previously, I found out that the rate of reaction between Sodium Thiosulphate and Hydrochloric acid depends on the amount of concentration, which becomes faster with a higher volume of concentration. [IMAGE]Mg + 2HCL MgCl2 + H2 This equation shows the reaction that will occur Apparatus: Magnesium ribbon 2M Hydrochloric acid Distilled water Stop clock Conical flask Delivery tube Measuring cylinder Measurements: Here are the measurements of the hydrochloric acid and the magnesium ribbon, which I am going to use in the experiment. Hydrochloric acid 1. 50cm³ of hydrochloric acid 2.
About 1/100 volumes are injected for capillary columns by split/ splitless injection which small fixed fraction of sample are deliver to the column and the remainder are going to waste (SHU, 2014).Separation occurs as the vapour constituents equilibrate between carrier gas and the stationary phase (Christian, ***). The carrier gas is chemically inert gas such as argon (Ar), helium (He), or nitrogen (N). The best efficiency is when the density if gas is high but a low-density gas gives a faster speed. The gas used is determined by the type of detector. As the sample emerges from the column at a constant flow rate, the sample is automatically detected.