If the reaction is first order, its graphical representation is seen as ln[A] (natural log of concentration) vs. time, and the slope of its like is also the negative rate constant. Finally, for a second order reaction the graph is shown as 1/[A] (inverse of concentration) vs. time, and the slope of its given line is the positive rate constant. By understanding the rate law and finding the value of the correct rate constant with respect to the order of the reaction, one can determine the half-life of the crystal violet. This is because the crystal violet undergoes a decay reaction with the sodium hydroxide. According to Beer's Law, the absorbance of crystal violet is proportional to its concentration.
25 cm3 of a solution of sodium hydroxide reacts with 15 cm3 of 0.1 mol/dm3 HCl. What is the molar concentration of the sodium hydroxide solution? 4. Succinic acid has the formula (CH2)n(COOH)2 and reacts with dilute sodium hydroxide as follows: (CH2)n(COOH)2 + 2NaOH → (CH2)n(COONa)2 + 2H2O 2.0 g of succinic acid were dissolved in water and the solution made up to 250 cm3. This solution was placed in a burette and 18.4 cm3 was required to neutralise 25 cm3 of 0.1 moldm-3 NaOH.
Computer Additivity of Heats of Reaction: Hess’s Law 18 (1) Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. (2) Solid sodium hydroxide reacts with aqueous hydrochloric acid to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) ) + Cl–(aq) → H2O(l) + Na+(aq) + Cl–(aq) ∆H2 = ? OBJECTIVES • • • • In this experiment, you will Combine equations for two reactions to obtain the equation for a third reaction. Use a calorimeter to measure the temperature change in each of three reactions.
This reaction can be summed up using the following formula: 5Fe2++8H++MnO4- →5Fe3++Mn2++4H2O After standardization, the potassium permanganate solution is then titrated with 3 different magnesium oxalate solutions. To find the concentration of the C2O42- the balanced net ionic redox reaction formula is used: 5C2O42-+16H++2MnO4- →10CO2+2Mn2++8H2O It is important to note the addition of sulfuric acid (9M H2SO4) in performing this experiment because of the following reasons: 1) Sulfuric acid keeps the iron (II) from air oxidizing into iron (III) 2) Sulfuric acid keeps the iron (II) from hydrolyzing into Fe(OH)2 3) Sulfuric
==> NaHCO3(aq.) + NaCl(aq.) We will standardize the HCl solution to use it in the titration. The standardization will come as a result of the 1:1 molar ratio above. Thus, the molarity of the HCl solution can be calculated by dividing the number of moles of HCl by the volume of HCl (in liters) used to neutralize the Na2CO3 .
________________________________________ Chart 1.2: the difference between the readings in each of the trails. Chart 1.3: the difference between the sum and the average. CONCLUSION AND EVALUATION CONCLUSION: Equivalence point is the point at which the moles of H+ is equal to the moles of OH+,an indicator is used to show the equivalence point during a titration. in a titration the method is about totaling one reactant from the burette (regularly the acid),to a known volume of the other reactant in a conical flask(regularly the base) . In order to find the concentration of NaOH we need to tag along the following steps: a- note down the balanced chemical equation for the reaction C8H5O5K+NaOH→C8H4O4KNa+H2O b- pull out applicable information from the experiment: C8H5O5K V=0.025 dm3 C=0.2M NaOH V=0.021 dm3 C= ??
Micro – scale Reduction of a Ketone to an Alcohol: Benzophenone to Diphenylmethanol with Sodium Borohydride Abstract: Purpose of experiment 2.1 was to perform reduction reaction of benzophenone to diphenylmethanol with sodium borohydride as a reducing agent. The reducing agent was used in excess to ensure complete reduction of the carbonyl group. The product was isolated as a solid by filtration and its purity was checked using Thin Layer Chromatography with different ratios of mixture of polar and non – polar solvents and by checking its melting point, which was 520C - 620C. Infra – Red spectroscopy was not performed, however previously printed graphs were compared and analysed based on tables in Chemistry Laboratory Manual. Purpose of the Experiment: To produce diphenylmethanol from the reduction of benzophenone by using sodium borohydride as a reducing agent.
The values found for KH+ for the reaction using HCl as the acid were found to be (i)KH+ = 4.96x10-5, (ii)KH+ = 1.24x10-5, (iv)KH+ = 1.84x10-5. The KHA value for the reaction using ClCHCOOH as the acid was found to be (iii) KHA = 2.985. Introduction: The aim of this experiment is to perform a titration of an acid, HCl/ClCHOOH against Na2S2O3. Form plotting the results we then want to find Kobs for each reaction and KH+/KHA for the reactions. Kobs is the slope on the graph plotting Vol of NaaS2O3 against time.
Experiment: Cyclohexanone from Cyclohexanol aq Abstract: The primary objective of this experiment was to create cyclohexene from the dehydration of cyclohexanol with phosphoric acid. Through the use of simple distillation it was possible to separate the solution. The Agilent 7890A Gas Chromatography System was used to determine the purity of the distillate which verified the success of the separation. Introduction: Alkenes can be prepared by from alcohols by an acid catalyzed dehydration reaction. In the experiment a secondary alcohol (cyclohexanol) is heated with acid (phosphoric acid).
Results : Yield (mass in gram) = __________________0.128 g_____________________ Melting point of pure phenyl benzoate (OC) = ___________70O______________ Melting point of your phenyl benzoate (OC) = ___________69O______________ Questions : 1. Why do we use NaOH solution to dissolve phenol rather than water in step 1 ? Because NaOH can be use to change the phenol to ion form, which can be more soluble in the aqueous