Why does the colour of potassium permanganate not disappear when excess is added

Table of Contents • • • • • • • • Why does the colour of potassium permanganate not disappear when excess is added? Initially colour disappears because colouredpermanganate ions of potassium permanganate are consumed to oxidiseethanol. When excess is added colour does not change because there is nomore alcohol left and hence there is noreaction. Why does water become Coloured when crystals of potassium permanganate is added? Answer: Because of the collision of water molecules. Explanation: When potassium permanganate crystals are introduced in the water, the water molecules collide with the surface of the crystals and thus the water becomes coloured. What colour does potassium permanganate change to? purple Given that potassium permanganate changes the colour from purple to colourless. The chemical formula of potassium permanganate is $KMn$ . Potassium permanganate is made up from potassium ion and permanganate ion. The purple colour of the potassium permanganate is due to permanganate ion. Why does the color of KMnO4 change at the end of the estimation of Fe II by redox titration? In redox titrations, we titrate a substance with a reducing nature against a substance with an oxidising nature. KMnO4 is an oxidant. It reacts and reduces the other substance. The colour of manganese compounds largely depends on the oxidation state. What is the reason that solution of potassium permanganate remains Coloured even after large number of dilutions? Answer: Potassium permanganate so...

[ "article:topic", "vanillin", "authorname:nicholsl", "TLC Plates", "Permanganate", "iodine", "p-Anisaldehyde", "Phosphomolybdic Acid (PMA)", "Iron(III) Chloride", "Bromocresol Green", "Visualizing TLC", "showtoc:no", "license:ccbyncnd", "licenseversion:40", "source@https://organiclabtechniques.weebly.com/" ] \( \newcommand\) • • • • • • • • • • • • • • • • • • • • • Organic compounds most commonly appear colorless on the white background of a TLC plate, which means that after running a TLC, chemists often cannot simply see where compounds are located. The compounds have to be "visualized" after elution, which means to temporarily convert them into something visible. Visualization methods can be either non-destructive (compound is unchanged after the process) or destructive (compound is converted into something new after the process. Viewing a TLC plate under ultraviolet light is non-destructive, while using a chemical stain is destructive. Visualization Summary Below is a summary of various visualization techniques, and the functional groups that generally react with each. A more detailed discussion of each technique is provided later in this section. UV Light: For aromatics + conjugated systems Iodine: Visualizes ~half the time. Strongly reacts with aromatics p -Anisaldehyde : For many aldehydes, ketones, and alcohols Vanillin: For many aldehydes, ketones, and alcohols Permanganate: For alkenes, alkynes, or oxidizable groups (aldehydes, alcohols) Phosphomolybdic Acid (PM...

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In the redox titration of $\ce I am not sure which of them occur in reality. So, which of the reactions are the reasons for the 30 second rule? And why is it 30 second anyway? Why not 40 second or 1 minute? The most likely reason for the colour of permanganate to vanish after a few seconds even though you thought you have the end point is: you have not reached the end point. Acid/base reactions are typically extremely fast reactions; their rate is not even limited by the speed of diffusion since protons can be shuffled along via the With practically all other reactions that is not the case. They are typically slower and can be much slower. The reacting species must meet each other in solution which can take time. At the beginning of the titration, there are still many iron(II) ions floating around ready to be oxidised by any incoming permanganate. Towards the end, iron(II) is getting more scarce. So a permanganate ion may linger around much longer before it meets an iron ion. You should give it a certain time in case it does find one. The value of $\pu$ is arbitrary. Ten seconds or two minutes would probably do equally well (except that ten seconds may or may not be slightly on the short side). The book/method just needs to present any ballpark value. So the reaction occuring that causes the discolouring of the solution is indeed exactly the reaction you are observing: the oxidation of iron(II). It is merely slowed down so it can take a few seconds to proceed to completion...

Tests for Unsaturation Table of Content Functional group plays a vital role in determining the nature of the organic compounds and their properties. Identification of functional groups is a very important part of qualitative analysis. Tests for unsaturation can be used to identify the double and triple bonds present in the organic compound. Aim: To identify the presence of functional group like test for saturation and unsaturation in a given organic compound. Theory: Organic compounds containing carbon and hydrogen are called hydrocarbons. Most of the organic compounds are derived from hydrocarbons by the displacement of one or more hydrogen atoms by single atom or a group of atoms such as acid, aldehyde, Hydroxide and halogen functional groups etc. Also Read: 1. Saturated Hydrocarbons Saturated hydrocarbons molecules which have no double bonds in them are called saturated or commonly called alkanes. This simply means that there are as many hydrogen atoms as possible in the molecule, and no more can be added. They are also called paraffins and least reactive. Saturated hydrocarbon has long chains as well as branched ones and further classified as aliphatic hydrocarbons and cycloalkanes. Some examples are methane, ethane, propane and butane. 2. Unsaturated Hydrocarbons In organic compounds unsaturation is due to the presence of double and triple bonds. The aliphatic hydrocarbons that contain a double bond between the two carbon atoms are called alkenes and the hydrocarbons ...