Acid Base Indicator Lab Report

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Introduction:
In this experiment acid base indicators will be tested, using a red cabbage mixture. Substances can be classified as acidic or alkalinic depending on the concentration of hydrogen or hydroxide ions. The higher the concentration of hydrogen ions the lower the pH this means it will be an acid and the higher the concentration of hydroxide ions the higher the pH this means it will be an base(science prof online). A pH indicator is a solution or mixture that changes colour in the presence of an acid or base. Red cabbage contains a specific pigment called flavin(science kiddo), in acidic conditions this pigment will turn a red colour and in basic conditions it will turn a green colour. From this it is noticeable that the colour change
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In the experiment the lemon juice tested to be the strongest acid with a pH of 2 and the pink colour change, the weakest acid was ENO antacid tablets with a pH of 6.1 accompanied by a violet colour change. . In the experiment the Handy Andy or ammonia tested to be the strongest base with a pH of 11.6 and a green colour change, the weakest base was baking powder with a pH of 8 accompanied by a blue-ish purple colour change. And it was also tested that water was slightly acidic with a pH of 7.2. An acid is considered to be a proton donor, this means it dissociates into hydrogen ions in a solution (Wikipedia), this will correspond to it having a sour taste and sharp odour. A base is considered to be a proton accepter, this means it dissociates into hydroxide ions in a solution (Wikipedia), this will correspond to it having a bitter taste and no scent. Acids add more hydrogen ions to a solution, while bases remove hydrogen ions from a solution, so the pH can be adjusted to any value wanted by carefully combining acids and bases together, if a vinegar solution that is strongly acidic is present, the pH can be raised by slowing adding a base like ammonia which will remove some of the extra hydrogen ions from the solution. If just a little was added the pH might change from 2 to 5, making a weaker acid, but by adding a little more base enough hydrogen ions is removed to raise the pH to 7 or neutralize the solution, also by adding even more base more hydrogen ions can be removed, raising the pH until the solution becomes a strong base (Coolscience). Experiments are replicated too ensure accurate results and to verify uncertain results it also helps to refine experimental observations (ochemonline). The most common pH testing in laboratories is a device called a probe and meter, commonly

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