A universal indicator is a blend of pH indicator solutions designed to identify the pH of a solution over a wide range of values. Methyl orange or phenolphthalein are used because they give a sudden change in colour at neutralisation which makes it easier to see the end point of the titration. Using the Universal Indicator: You can select the aqueous solution type you want to find the pH value of, from the ‘Select Aqueous Solution’ drop down list (vegetable & fruit juices, household items, acids and bases in the lab or salts in water). On a universal indicator test, HCl would come out as red. Big Idea Acid-base indicators, such as red cabbage juice, turn different colors in acidic and basic solutions due to a pigment molecule called anthocyanin. There are several different formulas for universal indicators, but most are based on a patented formula developed by Yamada in 1933. A common mixture includes thymol blue, methyl red, bromothymol blue, and phenolphthalein. Therefore, it can be used to determine the acidity or the alkalinity of a solution. There are many universal indicators available, but the most common universal indicator is a mixture of following pH indicators. Knowledge of reaction mechanisms is not required, 4:07 know that crude oil is a mixture of hydrocarbons, 4:08 describe how the industrial process of fractional distillation separates crude oil into fractions, 4:09 know the names and uses of the main fractions obtained from crude oil: refinery gases, gasoline, kerosene, diesel, fuel oil and bitumen, 4:10 know the trend in colour, boiling point and viscosity of the main fractions, 4:11 know that a fuel is a substance that, when burned, releases heat energy, 4:12 know the possible products of complete and incomplete combustion of hydrocarbons with oxygen in the air, 4:13 understand why carbon monoxide is poisonous, in terms of its effect on the capacity of blood to transport oxygen references to haemoglobin are not required, 4:14 know that, in car engines, the temperature reached is high enough to allow nitrogen and oxygen from air to react, forming oxides of nitrogen, 4:15 explain how the combustion of some impurities in hydrocarbon fuels results in the formation of sulfur dioxide, 4:16 understand how sulfur dioxide and oxides of nitrogen oxides contribute to acid rain, 4:17 describe how long-chain alkanes are converted to alkenes and shorter-chain alkanes by catalytic cracking (using silica or alumina as the catalyst and a temperature in the range of 600–700⁰C), 4:18 explain why cracking is necessary, in terms of the balance between supply and demand for different fractions, 4:19 know the general formula for alkanes, 4:20 explain why alkanes are classified as saturated hydrocarbons, 4:21 understand how to draw the structural and displayed formulae for alkanes with up to five carbon atoms in the molecule, and to name the unbranched-chain isomers, 4:22 describe the reactions of alkanes with halogens in the presence of ultraviolet radiation, limited to mono-substitution knowledge of reaction mechanisms is not required, 4:23 know that alkenes contain the functional group >C=C<, 4:24 know the general formula for alkenes, 4:25 explain why alkenes are classified as unsaturated hydrocarbons, 4:26 understand how to draw the structural and displayed formulae for alkenes with up to four carbon atoms in the molecule, and name the unbranched-chain isomers. Universal indicator is used to make pH paper, which can be used to quickly test solutions for their approximate pH. Knowledge of cis/trans or E/Z notation is not required, 4:27 describe the reactions of alkenes with bromine, to produce dibromoalkanes, 4:28 describe how bromine water can be used to distinguish between an alkane and an alkene, 4:29 (Triple only) know that alcohols contain the functional group −OH, 4:30 (Triple only) understand how to draw structural and displayed formulae for methanol, ethanol, propanol (propan-1-ol only) and butanol (butan-1-ol only), and name each compound, the names propanol and butanol are acceptable, 4:31 (Triple only) know that ethanol can be oxidised by: burning in air or oxygen (complete combustion), reaction with oxygen in the air to form ethanoic acid (microbial oxidation), heating with potassium dichromate(VI) in dilute sulfuric acid to form ethanoic acid, 4:32 (Triple only) know that ethanol can be manufactured by: 1) reacting ethene with steam in the presence of a phosphoric acid catalyst at a temperature of about 300⁰C and a pressure of about 60–70atm; and 2) the fermentation of glucose, in the absence of air, at an optimum temperature of about 30⁰C and using the enzymes in yeast, 4:33 (Triple only) understand the reasons for fermentation, in the absence of air, and at an optimum temperature, 4:34 (Triple only) know that carboxylic acids contain the functional group -COOH, 4:35 (Triple only) understand how to draw structural and displayed formulae for unbranched- chain carboxylic acids with up to four carbon atoms in the molecule, and name each compound, 4:36 (Triple only) describe the reactions of aqueous solutions of carboxylic acids with metals and metal carbonates, 4:37 (Triple only) know that vinegar is an aqueous solution containing ethanoic acid, 4:38 (Triple only) know that esters contain the functional group -COO-, 4:39 (Triple only) know that ethyl ethanoate is the ester produced when ethanol and ethanoic acid react in the presence of an acid catalyst, 4:40 (Triple only) understand how to write the structural and displayed formulae of ethyl ethanoate, 4:41 (Triple only) understand how to write the structural and displayed formulae of an ester, given the name or formula of the alcohol and carboxylic acid from which it is formed and vice versa, 4:42 (Triple only) know that esters are volatile compounds with distinctive smells and are used as food flavourings and in perfumes, 4:43 (Triple only) practical: prepare a sample of an ester such as ethyl ethanoate, 4:44 know that an addition polymer is formed by joining up many small molecules called monomers, 4:45 understand how to draw the repeat unit of an addition polymer, including poly(ethene), poly(propene), poly(chloroethene) and (poly)tetrafluroethene, 4:46 understand how to deduce the structure of a monomer from the repeat unit of an addition polymer and vice versa, 4:47 explain problems in the disposal of addition polymers, including: their inertness and inability to biodegrade, the production of toxic gases when they are burned, 4:48 (Triple only) know that condensation polymerisation, in which a dicarboxylic acid reacts with a diol, produces a polyester and water. 2. To measure the strength of an acid or a base solution we use universal indicators. For use as laboratory reagent. Y… The common application of indicators is the detection of end points of titrations. Universal indicator and the pH scale Universal indicator is supplied as a solution or as universal indicator paper . However, universal indicator is used to find the strength of the substance by denoting its pH value. Universal indicator, which is actually a mixture of several indicators, displays a variety of colours over a wide pH range so it can be used to determine an approximate pH of a solution but is not used for titrations. They are cheap, rapidly produce a result that is good to about a pH unit and can simply be discarded after use. 4:49 (Triple only) Understand how to write the structural and displayed formula of a polyester, showing the repeat unit, given the formulae of the monomers from which it is formed, including the reaction of ethanedioic acid and ethanediol: 4:50 (Triple only) know that some polyesters, known as biopolyesters, are biodegradable, (d) Energy resources and electricity generation, 2:31 know that acids in aqueous solution are a source of hydrogen ions and alkalis in a…, 4:37 (Triple only) know that vinegar is an aqueous solution containing ethanoic acid, 2:48 describe tests for these anions: Cl⁻, Br⁻ and I⁻ using acidified silver nitrate…, 1:56 (Triple only) understand why ionic compounds conduct electricity only when molten or in…, 2:47 describe tests for these cations: NH₄⁺ using sodium hydroxide solution and identifying…, 1:43 Know that ionic compounds do not conduct electricity when solid, but do conduct…, d) Relative formula masses and molar volumes of gases, e) Chemical formulae and chemical equations, b) Group 1 elements: lithium, sodium and potassium, c) Group 7 elements: chlorine, bromine and iodine, d) The industrial manufacture of chemicals. 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