The goal of the experiment is to synthesize a bromohexane compound from 1-hexene and HBr(aq) under reflux conditions and use the silver nitrate and sodium iodide tests to determine if the product is a primary or secondary hydrocarbon. The heterogeneous reaction mixture contains 1-hexene, 48% HBr(aq), and tetrabutylammonium bromide and was heated to under reflux conditions. Heating under reflux means that the reaction mixture is heated at its boiling point so that the reaction can proceed at a faster rate. The attached reflux condenser allows volatile substances to return to the reaction flask so that no material is lost. Since alkenes are immiscible with concentrated HBr, tetrabutylammonium bromide is used as a phase-transfer catalyst.
In redox reaction, one element or compound is reduced and gains electrons, while on the other hand, the other element or compound is oxidized and loses electrons. For this lab, through the given oxidation and reduction numbers from balancing the equation and the electrons, it was shown that Manganese was reduced while Iron was oxidized. Also from the equation, the movement of electrons can be noticed, as it was added or subtracted from the substances. In order to balance an equation, there must be same number of elements on both sides, with the exception of hydrogen and oxygen. From there, in order to balance oxygen, water molecules are enumerated to the opposite of the equation/reaction.
The % RSD was 1.1% based on the three closest endpoint values. Having used all the values collected, the RSD would have certainly been much larger as the other two values were much larger than the three included in the average. An indicator is a substance that undergoes a change of color when the equivalence point of a titration is reached. It is useful to use an indicator in a titration because the indicator allows the experimenter to know when the equivalence point (which should signify the end of the titration) is reached. Without the indicator, the titration would not work because the person performing the titration would not know when to stop titrating.
Also, the resistance to high temperatures and pressures allow it to go through the metamorphic processes unscathed. Experiment 11 concepts are heavily used in this experiment. The concept of using the MeasureNet Spectrophotometers, analyzing resulting graphs to compare and contrast differing solutions of λ max (or lambda max), therefore comparing and contrasting differing solution wavelengths. Through comparing an “unknown solution” to the known solutions wavelengths, students are able to determine in this particular experiment if chromite is present in the unknown given metal ore sample. If the wavelengths of the unknown metal ore solution share a lambda max or maximum wavelength to the lambda
But these usually require large amounts of sample and chemical extraction. Also levels of OT obtained by this method are close to the detection limit for the assay leading to errors. Thus an enzyme-immunoassay (EIA) would be better suited for OT detection. Detection of salivary OT using a commercial EIA kit with minimal cross reactivity and a lower detection limit of 4.68 pg/ml was described by Carter, C.S., et al. Prior to the assay, the samples were concentrated fourfold to ensure that the OT levels would be within the
Enzymes work using a simple ‘Lock and Key’ theory this is when to substances fit together perfectly because of their shape and size, the theory is demonstrated in the diagram below: Temperature is very important to productivity of the enzyme reactions. If the temperature is too high they move around too fast and there are less successful collisions; if the temperature is too low then they move around slowly and therefore collide less often which in turn creates less successful collisions. There are several factors which can affect how fast an enzyme reacts these are temperature, mass and surface area. Out of these three we have chosen to investigate the surface area. We will be using the enzyme from the liver and placing it in hydrogen peroxide, this will create oxygen and water, we will measure the amount of oxygen produced we will catch and measure it in a measuring cylinder.
To perform this experiment, we will utilize emission spectra, titrations, and thermal gravimetric analysis, using knowledge from Experiments 10, 4, Titrations of Na2CO3 and NAHCO3 by HCl (hydrochloric acid) will be performed to determine the concentration of HCl, as well as the number of moles of HCl present within the sample of baking soda. As a result, we will be able to determine the molar concentration of HCl by determining its equivalence point (the point on the graph where the exact amount of rectant needed to perform a reaction has been added) from graphical analysis. Na2CO3(aq.) + HCl(aq.) ==> NaHCO3(aq.)
In this case we need the dienophile to be cis for this reaction to proceed because the two molecules need to approach each other at an angle parallel to each other. This forms new sigma bonds and reduces the number of pi bonds which are less favorable to a molecule. The mechanism itself is a concerted one, meaning that there is no intermediate. The fact that the conjugated dienes are so reactive are due to the pi system from the
Experiment 2 : Experimental Applications of Hess’s law Objectives: 1. To find the enthalpy change of solid sodium chloride by using Hess’s law. 2. To apply q = m x c x ∆T in the calculations of enthalpy change for a reaction. Introduction: Calorimeter is a device which is used to determine the heat release or absorb in a chemical reaction.
Evaluation This was a very smooth and easy going procedure, even though the set up involved a lot little steps to do it correctly. If one step was skipped or wrongly followed, the entire trial would have to be repeated. For that reason, I made the method crystal clear, to assure that everyone can repeat it. My first draft of the method was very different from the final one, seeing that once I tried it out, I realised the many details that must be payed attention to. I changed the procedure into a two part procedure, and added steps such as titling the beaker, and only removing you’re hand once the graduated cylinder is deep inside the beaker.