Tuesday, November 26, 2019

How to find the molarity of the acid Essay Example

How to find the molarity of the acid Essay Example How to find the molarity of the acid Essay How to find the molarity of the acid Essay We are going to do an experimentation using the technique of titration to find the concentration of solutions this is a way of measuring quantities of reactants and is useful for finding an unknown concentration .we know that an acid will react with a base so thats why we will do titration. Titration enables the reacting volumes of two solutions to be accurately found one solution is found with a pipette which slowly drops the one solution in to a conical flask of another solution and the complete reaction is shown with an indicator.At which the colour changes is called the end point. We want to find the mole ratios of the reactants and products shown by the balanced chemical equation there should be no any side reactants taking place, as these will affect our measurements. The reactant mixture must be quenched to slow down or stop the reaction. Using a base could neutralize an acid catalyst.SafetyThis experiment sodium hydroxide will be used this is a strong alkaline and can damage the skin and can also damage the eyes if splashed in them so during the experiment so I will be using safety goggles during all times I will also wear rubber gloves to protect the skin from any contact with the sodium hydroxide.EquipmentThis is the equipment that I will be using:Pipette, beaker, a white ceramic tile, a clamp and stand, burette, methyl orange. And a 250 ml standard measuring flask and some electronic scales.MethodIn this experiment I want to find out the concentration of the hydrochloric acid (HCl) with the concentration of the NaOH and used a indicator to tell me when neutralization had taken place.I had to gather a pipette, beaker, a white ceramic tile, clamp and stand, burette, methyl orange and a 250 ml standard measuring flask and some electronic scales. I got some NaOH and weighed out 3.3 grams on the electric scales. I poured 250 ml of distilled water into my standard measuring flask and then placed the NaOH pellets into the 250 ml of distilled water the pelle ts are hydroscopic and absorb water from the atmosphere around them so I had to move quickly at this stage.I set up my clamp and stand and clamped the graduated burette and I put on my goggles. I measured out 25 ml of HCl and put this into the pipette. I then used the pipette to measure about 25 ml of NaOH and then this was poured this into a conical glass. I put three drops of methyl orange to the NaOH and stirred it around until the solution changed orange. I placed the conical glass under the burette and placed a white tile underneath the conical glass to help me watch me the indicator change colour.I made a results table the first time this experiment would be conducted it would be the rough to give me an indication of when to stop the burette then I would repeat it three times. While the HCl was being gradually dropped into the conical flask I had to continually had to swirl the NaOH and methyl orange solution until the colour changed from yellow to orange. When I went past thi s point of adding too much HCl the colour would go to red this was known as the end point. I found on the first time of conducting this experiment I found at around about 17cm3 was where I needed to stop graduating the solution into the conical flask.Results tableRough1st attempt2nd attempt3rd attempt17.817.117.017.1The average was 17.061 mol of NaOH = 40 gx mol of NaOH = 3.3 g3.3 g /40 g = x0.0825 = x mol0.0825 mol of NaOH dissolved in 250 ml (0.25dm 3) distilled water0.25 dm 3 =0.0825 mol1 dm 3 = x mol0.0825 x 1 /0.25 = x mol=0.33 mol /dm3Finding the concentration of hydrochloric acidMAVA = a MA x 0.01706 = 1MBVB = b 0.33 x 0.025 = 1MA x 0.01706 x 1 = 0.33 x 0.025 x 1MA x 0.01706 = 0.00825MA = 0.008250.01706MA = 0.48 mol/dm3ConclusionI found out that the concentration of hydrochloric acid is 0.48 mol/dm3 . the experiment was repeated three times and the results obtained did not differ from no more than 0.1 . this proved that the experiment was carried out carefully and the results were accurate.EvaluationIn this experiment I feel that I should have dried out the conical flask after cleaning it out with the distilled water as this has most likely affected the concentration of the NaOH. I should have also cleaned and dried out the graduated burette as this also could have affected the final results but this would have proved to be too difficult as it was very narrow and long I dont think that I could have read a tenth of a cc on the graduated pipette of the water that I could not have dried out. All the experiments were conducted on the same day so the room temperature stayed the same.

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