{"id":14498,"date":"2020-12-01T09:38:27","date_gmt":"2020-12-01T04:08:27","guid":{"rendered":"https:\/\/cbselibrary.com\/?p=14498"},"modified":"2020-12-01T09:49:09","modified_gmt":"2020-12-01T04:19:09","slug":"explain-effect-concentration-rate-reaction","status":"publish","type":"post","link":"https:\/\/cbselibrary.com\/explain-effect-concentration-rate-reaction\/","title":{"rendered":"Explain the effect of concentration on the rate of reaction?"},"content":{"rendered":"
<\/p>\n
Effect of concentration on the rate of reaction:<\/strong><\/p>\n Other suitable reactions to study the effect of concentration on the rate of reaction.<\/p>\n Table illustrates some examples. People also ask<\/strong><\/p>\n Aim:<\/strong> To investigate the effect of concentration on the rate of reaction. Results: Interpreting data:<\/strong> Discussion:<\/strong><\/p>\n Conclusion:<\/strong> <\/p>\n","protected":false},"excerpt":{"rendered":" Explain the effect of concentration on the rate of reaction? Effect of concentration on the rate of reaction: When the concentration of a reactant increases, the rate of reaction also increases. (a) For example, two sets of experiments are carried out using the reacting conditions below: Set I: 1 g of zinc powder and … Read more<\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":""},"categories":[84],"tags":[5542,5576,5578,5577,5540,5543,5537,5538,5541,5539,5584,5536,5507,5535],"yoast_head":"\n\n
\nSet I:<\/strong> 1 g of zinc powder and 20 cm3<\/sup> of 0.4 mol dm–<\/sup>3<\/sup> hydrochloric acid at room temperature.
\nSet II:<\/strong> 1 g of zinc powder and 20 cm3<\/sup> of 2 mol dm–<\/sup>3<\/sup> hydrochloric acid at room temperature.
\n(b) The rate of reaction of set I is higher<\/strong> than that of set II.
\n(c) This is because the concentration<\/strong> of hydrochloric acid used in set I is higher<\/strong> than that in set II.<\/li>\n\n
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\n<\/p>\n\n
How does concentration affect the rate of reaction experiment<\/strong><\/h2>\n
\nProblem statement:<\/strong> How does the concentration of a reactant affect the rate of reaction?
\nHypothesis:<\/strong> When the concentration of a reactant increases, the rate of reaction becomes higher.
\nVariables:<\/strong>
\n(a) Manipulated variable : Concentration of sodium thiosulphate solution
\n(b) Responding variable : Rate of reaction
\n(c) Controlled variables : Temperature, total volume of the reacting mixture, concentration and volume of sulphuric acid, size of conical flask
\nOperational definition:<\/strong>
\nRate of reaction is inversely proportional to the time taken for the mark ‘X’ to disappear from sight.
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\nMaterials:<\/strong> 0.2 mol dm–<\/sup>3<\/sup> sodium thiosulphate solution, 1.0 mol dm–<\/sup>3<\/sup> sulphuric acid, distilled water, white paper with a mark ‘X’ at the centre.
\nApparatus:<\/strong> 150 cm3<\/sup> conical flasks, 50 cm3<\/sup> measuring cylinder, 10 cm3<\/sup> measuring cylinder, digital stopwatch (electronically operated with an accuracy of 0.01 s).
\nProcedure:<\/strong><\/p>\n\n
\n<\/li>\n
\n<\/strong>
\n<\/p>\n
\nBased on the results obtained, two graphs<\/strong> are plotted.
\n(a) Graph I:<\/strong> Graph of the concentration of sodium thiosulphate solution against time, as shown in figure.
\n(b) Graph II:<\/strong> Graph of the concentration of sodium thiosulphate solution against 1\/time, as shown in figure.
\n<\/p>\n\n
\n<\/li>\n
\n<\/li>\n
\n(b) Hence, it infers<\/strong> that as the concentration<\/strong> of sodium thiosulphate solution becomes lower,<\/strong> the rate<\/strong> of reaction also decreases.<\/strong><\/li>\n
\n(b) Since rate of reaction is directly proportional to 1\/time, it can be deduced that:
\nRate<\/strong> of reaction is directly proportional<\/strong> to the concentration<\/strong> of sodium thiosulphate solution.
\n(c) In other words:
\nWhen the concentration<\/strong> of a reactant increases,<\/strong> the rate<\/strong> of reaction becomes higher.<\/strong><\/li>\n
\n(b) If the 150 cm3<\/sup> conical flasks are replaced by bigger 250 cm3<\/sup> conical<\/strong> flasks,<\/strong> the time taken for the mark ‘X’ to disappear from sight becomes longer.<\/strong>
\n(c) This is because the base area of the 250 cm3<\/sup> conical flask is bigger and the depth of the 50 cm3<\/sup> solution becomes shallower. Hence, a bigger amount of sulphur precipitate is required to cause the mark ‘X’ to disappear from sight.<\/li>\n
\n(b) This is because hydrochloric acid is a strong monoprotic acid,<\/strong> whereas sulphuric acid is a strong diprotic acid.<\/strong> Hence, the concentration of hydrogen ions in hydrochloric acid is only half<\/strong> the concentration of hydrogen ions in sulphuric acid.<\/li>\n
\nWhen the concentration of a reactant increases, the rate of reaction also increases. Hence, the hypothesis can be accepted.<\/p>\n