Determining the Concentration of Sulphuric Acid Essay Example for Free

Determining the tightfistedness of Sulphuric Acid tasteI am dismissal to plan an experiment to determine the accurate dumbness of sulfuric battery- venereal disease. It is melodic theme to corroborate the concent symmetryn mingled with 0.05 and 0.15 moldm-3. I pass on be provided with a solid base which is anhydrous (powder) atomic number 11 change (Na2CO3). To find the accurate concentration I volition titrate the sulphuric pungent against the atomic number 11 carbonate. The reaction following ordain take placeNa2CO3 (aq) + H2SO4 (aq) Na 2 SO4 (aq) + CO2 (g) + H2O(l)1deciding the AmountsSulphuric acid has a concentration ab come forward 0. 10 moldm-3 (half way between 0.05 and 0.15 moldm-3). I would standardised to substance abuse 25cm3 of sulphuric acid. This is because, it is not a wasteful measurement and also it would reduce percentage errors because this is kinda a large amount to use. It would be an ideal value to use.Further much, I will ask to bewild er up a standard result from the solid base that I have been provided with, which is sodium carbonate. I would again ideally like to use 25cm3 of the standard base per titer. This is because, the pipets have the rendering of 25cm3, which means the pipet is readily, available for this amount, thitherfore it is a sensible value.Consequently I will need to hold in up a standard solution of concentration 0.10moldm-3. This is because of the stoichiometry. The equation shows that for every one mole of sulphuric acid, there is one mole of sodium carbonate. Therefore, the concentration must be the same because the volumes ar the same and the emergence of moles atomic number 18 the same. I estimated the concentration of sulphuric acid to be 0.10 moldm-3 because its halfway between the thought amount of 0.05 and 0.15 moldm-3, therefore the concentration of the standard solution must be the same.Deciding what Indicator to UseI need to use an indication to see when the end point of the titration occurs, and they are employ between acid and alkalis. I have decided on victimization 2-3 drops of methyl group orange indicator fin my experiment per titre. This is because methyl orange indicator gives an accurate indication of the end point utilise a arduous acid (sulphuric acid) and a vague alkali (sodium carbonate). 2Making up my Standard SolutionAs I have mentioned before, I want my standard solution to have the concentration of 0.10 moldm-3. I have chosen my volumetric flaskful to be 250cm3. This is because these volumetric flasks are readily available. In addition, I am aiming to do rough five titrations, therefore this amount would allow me to do five titrations and have somewhat to spare.I right away need to find divulge how much sodium carbonate (Na2CO3) is needed to make a standard solution of concentration 0.10 moldm-3.I need to use the equation turn of events of moles = concentration (moldm-3) x volume(dm3)3n = c x vThe volume is 250cm3 so I need to burst this by 1000 so that it switch overs into dm3.Number of moles = 0.10(moldm-3) x 0.25 (dm3)Number of moles = 0.025 molesTherefore, 0.025 moles id required for the standard solution, nevertheless, I now need to convert this into grams by using the equationNumber of moles = Mass (g) / molar mass(gmol-1)4Mass (g) = Number of moles x Molar mass(gmol-1)Molar mass for Na2CO3 = (23 x 2) + 12 + (16 x 3) = 106gmol-1Mass (g) = 0.025 x 106 = 2.65gTherefore, 2.650g of sodium carbonate is required for my standard solution.My experimentThe apparatus I am going to use are as follows* Burette* Conical flask* Volumetric flask* Rubber ball pipette filler* Distilled water* Beakers* Filter funnel* Teat pipette* Tile* Sulphuric acid* sodium change* Scales* Spatula* Weighing bottle* Glass rod* Stand* Clamp* methyl group orange indicator curriculum of Experiment1. Prepare apparatus.2. Weigh a deliberateness bottle accurately. Using a spatula, transfer 2.650g of sodium carbonate to the weighing bottle and weigh again.3. Tip the contents of the weighing bottle into a whitened 250cm3 beaker and reweigh the empty weighing bottle to find the weight by difference. This way I back tooth hold out out the actual weight of sodium carbonate that has been transferred.4. Add 50cm3 of distilled water to the solid and stir using a glass rod until dissolved. Transfer this solution into a volumetric flask using a funnel. Make up the graduation mark with distilled water using a teat pipette to find out you so not wave-off it. This is now the standard solution.5. Put a stopper on the flask and invert it astir(predicate) 20 times to make sure all the solution is mixed.6. Using pipette filler, pipette 25.0cm3 of the solution into a novel conic flask.7. Clean the burette out with distilled water and thus again with sulphuric acid. Attach the burette to the stand, and fill the burette using a funnel with sulphuric acid.8. Add methyl orange indicator to the conical flash only about 2-3 d rops. Put the conical flask onto a white tile so the colour change is easy to see when titrating.9. quantify the solution until you reach the end point (when the solution turns orange), and record your results. I am going to use this as a rough titre.10. Repeat this to obtain concordant results, concordant meaning results that are interchangeable usually results which are in 0.1cm3 of each other.Risk AssessmentChemical NameForm applyprophylactic StatementPrecautionsSulphuric Acid0.05-0.15 moldm-3IrritantWear eye protection and gloves. Wear a lab coat. If spilt on skin dry with a textile and then wash with water. If spilt dry with cloth and then scrub using water. If it gets it contact with eyes wash them with water thoroughly. 6Sodium changeSolid and at0.10 moldm-3Irritant, but if dust gets in eyes its harmful.Wear safety goggles, gloves and also defensive clothing. If in contact with eyes wash quickly with clean water. If spilt on skin wash intensely. If inhaled travel to an area of fresh air. If spilt anywhere scoop as much as possible up. 5Methyl OrangeIndicator2-3 dropsIrritantWear safety goggles, gloves and also protective clothing. If spilt, clean it up using a cloth and water. If gets in contact with skin wash the area thoroughly. If registers eyes wash with clean water. 6Why my plan will Devise Reliable resultsMy plan will devise bona fide result because of many reasons. Firstly I am going to do a rough titre in my plan, which means I will have a rough idea of my titration, so when I do my real results I know when to add it drop wise, so that I wont overshoot the end point. Another reason why I wont overshoot the end point is because I am going to use a white tile so I can assess the end point more accurately.Furthermore, I am only going to add 2 or 3 drops of methyl orange indicator. This will make my results more reliable because the methyl orange indicator is slightly acidic, so it would use up the alkaline solution, therefore by only addi ng a exquisite amount of it will make my results more reliable and accurate.In addition, I am also going to wash my equipment out thoroughly with distilled water and then with the solution I am going to baffle that piece of equipment. This will remove any impurities that were originally in the containers so will make my results more reliable.Also, when I am measuring the solution, I will measure accurately by using a pipette to make sure the bottom of the meniscus is on the line to make my results more accurate. Also, when reading the burette I will put a piece of plain paper behind so I can read it more accurately.I will also, remember to take the funnel out of my burette as this could also affect the accuracy of my results. This is because drops are still on the funnel could enter my burette which mean more sulphuric acid affecting my results. This way by removing the funnel, I will achieve accurate results. 7Finally, I am going to use accurate equipment as possible, which will minimise errors in my results.Overall my results will be very accurate and reliableReferences1. Article on types of chemical reactions, http//www.sky-web.net/science/reaction-types. I utilise this to help me write my balanced equation for the reaction between sodium carbonate and sulphuric acid.2. Information on the use of indicators in acid-alkali titrations, salters practical assessment. I utilize this to decide what indicator to use as it told me what to use if I had a strong acid and weak alkali.3. Chemical ideas, 2nd edition, chapter 1, section 1.5, concentrations of solutions, published by Heinemann 2000. I used this to get the concentration equation.4. function point presentation on moles and concentration, http//moodle.kedst.ac.uk/mod/resource/view.php?id=4556. This helped me find the formulas for concentration and to find out the mass.5. Safety data sheet, http//www.brunnermond.com/products/sodium_carb. I used this source to find out the safety statement of sodium carbon ate and the precautions I will need to take.6. Hazard cards, numbers 98 and 32, Cleapps 1998 and 2003. I used these to find out the safety statement and also the precaution I will need to take when doing my experiment for methyl orange indicator and sulphuric acid.7. Skills for Salters as Chemistry, pages 3,4,6,7 and 29, chemistry department, 2007. I used this to see how I will use my equipment and use it accurately, giving me accurate results.AnalysisI made up my standard solution by firstly weighing out some sodium carbonate.I weighed the weighing bottle and added approximately 2.65g of sodium carbonate. I then transferred the sodium carbonate to a beaker and reweighed the weighing bottle, so I can therefore work out exactly how much sodium carbonate I transferred.Mass of weighing bottle and sodium carbonate = 57.732gMass of weighing bottle after transfer of sodium carbonate = 55.052gConsequently the accurate amount of sodium carbonate transferred is the mass of the weighing bottl e and the sodium carbonate, disconfirming the mass of the weighing bottle after the transfer which is57.932g 55.052g = 2.680gTherefore, 2.680g of sodium carbonate was transferred.Next I added about 50cm3 of water to the beaker and using a glass rod I stirred the solution until the sodium carbonate has dissolved. This was then fully transferred to a volumetric flask and water was added to the 250cm3 graduation mark. I then used a pipette to transfer 25.00cm3 of this standard solution to a conical flask and titrated with the unknown acid.I used 25.00cm3 of the standard solution for each titre after the experiment I had obtained results for how much acid was added for each titre. The results for how much acid I added for each titre are as follows 20.10cm3, 19.85cm3 and 20.05cm3. I am now going to work out an average by picking out the concordant results (results which are in 0.10cm3 of each other) and dividing by how many there is.20.10cm3+ 20.05cm3/2 = 20.075cm3.Therefore, my averag e titre was 20.075cm3. concentration of Sodium Carbonate SolutionI am now going to calculate the concentration of the sodium carbonate solution2.68g of sodium carbonate was dissolved in a 250cm3 volumetric flask using water, so I need to find out how many moles of the substance I used in differentiate to find out the concentration. Therefore I need to use the equationNumber of Moles= Mass (g)/Molar Mass (gmol-1)Molar mass of Na2CO3 = (23 x 2) + 12 + (16 x 3)= 106gmol-1Number of Moles= 2.680g/ 106gmol-1Number of Moles= 0.0253moles.Therefore, I used 0.0253 moles in my standard solution.I now need to use the equation to find the concentration constriction (moldm-3) = Number of moles/Volume (dm3)I firstly need to convert 250cm3 to dm3 so that my equation works1000cm3 = 1dm3250cm3 = 0.250dm3 (I change integrity by 1000).Concentration (moldm-3) = 0.0253moles/0.250dm3Concentration= 0.101moldm-3Consequently, I have calculated my sodium carbonate standard solution to have a concentration o f 0.101moldm-3, rounded to three significant figures.Concentration of acidI am now going to calculate the concentration of the acid solution therefore I firstly need to find out how many moles there is of the sodium carbonate solution, by using the equationConcentration of Na2CO3 (moldm-3) x Volume of Na2CO3(dm3) = Number of moles of Na2CO30.101moldm-3 x (25/1000) dm3) =0.00253 molesThe equation of my reaction isNa2CO3 (aq) + H2SO4 (aq) Na2SO4 (aq) + CO2 (g) + H2O(l)This equation shows that the molar ratio of sodium carbonate and sulphuric acid is 11 which means is there is 0.00253 moles of sodium carbonate there is 0.00253 moles in sulphuric acid.The average titre as shown above was 20.075cm3, which I need to convert to dm3 which is20.075cm3/1000 = 0.0201dm3.I can now use the equationConcentration (moldm-3)= Number of moles/Volume (dm3)Concentration (moldm-3)= 0.0253 / 0.0201Concentration = 0.126moldm-3.Overall, I conclude that the concentration of the acid solution is 0.126moldm-3 .