question 2(a) and question 3
Questions was the eriness remagent Explath. 2. How woll the following eruer affect year percent tepper and perocot alarine culculations (1oo high, tho low, of no effect)? In each case, eplain your asuwers. 4) A sudent miatukenly thooght the cerspound was alnety anby toes and dish't pciform itepe 14 b) The rine was sropped into the beaker and some of the solution so iplath oet. the arviation will be toe lew becate of He solilen Cmbeis eypper chonde whe be polach oud wad wal be lesx, thw vilt affect the Calculahon: c) The zine was renoved frem the solution befoee the solyine tamod ontorless. 50 he Nal te toe tom: d) The copter wase't ariod coerpletely mers and it all and to me ener all mat at ceppes. e) The copper was overheatod darieg dryieg low high, beouse of the ckeatde-e cuppor eisle which rerett incresicg in the 3. Uning your experimentally derived percen sompoedion (the nenage valses) and the mactived tugght in lecture, deternine the enginisal formuls of the copper chlonde. Percent copper in copper chloride, % Average Percent chlorine in copper chloride, % 1.71.1160=64.71%0.310.9100=33.33%35.29%264.71+33.36=49.02% Average So.9810 x51%= Show your work for determining the pereentages of chlorine and copper in Trial =1. Deternminatise of the rmpiricalformily The formals for the copper chlorils is cee the five shoin bekow. Calculate the prreent cornposition of each eotrpored. 63.546448.99939.4334phesstfCoy Bated on yoer cescrimsaulfy detcrnined pereent composition, which is the formela for the sample studicd todiay: Anhydroes empirical formals Denermination of ale ilsulowitformila. In the space belony, Actermine the ratio of water to copper chiloride for both trails, then ase the average ratio to deternine the fominila of the hydrated eompound in the kgdrated sample. Winlake the previoas page-and trost data shects in this co-orse-you'ec poing to have to beild yoar own data table. Be clrar and legibie. Formula of hydrated cepper chloride: Procedure 1. Renssemble the apparates from Part Iof Lab 5 . 2. Weigh yoer 50mL beaker, the use it to meteare agpoocimarely 2 grans of the copper chlonide. Reweigh the beaker with the sample. 3. Use your spatula to spread the sumple out as eveoly as eventy as you can, than beat the copper chloride unsil it's antydrous. 4. Similar to Lib 5. remove the beaker and allow it to cool ts fie a fim minutes. When it's cool enough to hasdle, reweigh it. 5. Add a senall amount of water to yoar beaker to dissolve any resital solid that was lef bet ind, then add it 10 the beaker. Add more water to the beaker entil you hare about 3040mL. of colutian. Stir to dissolve, 6. Take a piece of zinc and clean it with iandpuper or sieel wool to remove any dirt tecidue that aright have formed on the surfse of the metal. Cut a 2cm piese of clcan rine 7. Carefully place the rinc in the copper clleride soiumion. The copper aill form as a precip tate and the solution will tem colorless. Stir continuously to prevent the copper froen sticking to the zine. 8. Once the resetion is compleie, remove the zinc from solution. If ary obpper is sucuk to the rine. carefally serap it off, buck into the woluticn. 9. Tsolate the copper by decanting the solution into the 250mL beaker. 10. Wash the copper with appeoxinately 10 mit of water, stirning the miuturc and decint the water into the secend bcaker. 11. Heat your oopper to dry it. Do not overheat yoor solid, as this may emese it so rceit with oxygen in the air to form copper oxide (a black rolic). 12. When the copger appears dry, carefally remove the beaker and altion it to cool for aboet a minute or 5o, then reweigh it. Recond the conebinsed mass of the beaker and cogper. 13. Heat the sample for a lew more minutes, then weigh your sunple again. If the mams of the beuker and copper isn't wichin 0,1 g of the previoaly reconded mass, thete's still sose foutal water in your sampple. Contimae heating until your last tro mats are within 0 t gof cach echer. phore or the maction ay in vocwrine: Initial heating 31.2g32.2g 2nk heating 30.8g36.0g 3nt heating (if needed) 367 29.9 4b heating (if ncedod) Mass of copper, 8 1.1g0.3 Percent coppet in copper chloride, % 1.71.160=64.71%0.320.9100=35.33Averageincopperchlonide,%35.29%264.71+33.33=49.02%66.67%AverageSe.487.xsi7= Show your work for determining the percentages of thlorine and evpper in Trial a1. Determination of the empirinal formula The fommuln for the coper chlonide is one the five stown below. Calculate the percent consposition of each compoind. Bosed on your experimentally determisod percent compasition, which is the foemula for the rample stidied today. Anhydrous empinical formula CuC C2 Delermination of the Aydrated formula. In the space below, deternine the ratio of waser to eopper chloride for both trail, then use the average ratio wo determine the formuls of tie lydrated compound in tie tydiated sumple. Unilike the previous page - ind most data sbeets in this course- you're going wo have to build your own data table. Be clear and legerble. Formula of hydrated copper cliloride: Questions 1. Daring the converion of oopper chlonide to copeer, which rcactant was the limiting reagent and which was the excess nedgenr? Explain. 2. How woold the following erron affect yoer percent cegper and percent cllorine caleulations (too high. too low, of no effect)? In esch case, explain yoct atsiners. a) A student mistakenly thooght the compound was already anhyatrous and difn't perfiorm stept 14. b) The zinc was drepged inso the beaker asd socne of the solution to splash out e) The zine was temoved from the wolution before the solation tumed colorless: so ite weit da iteo tow d) The oopper wain't dried ceapletely too high, hecceje th the copfre unfit cinplehy ding the excris waler hets us du'n e) The copper was ovetheated darieg dryiog. loo hign, keave of the creation ef cepper exge which rejett iocremarg in He. Weigh of the espper decorwe die ogjes kons thi mil te nddest te dee dwvight too 3. Using your expertmentally derived peroent coepouition (the average values) and the mechod taeght in lectare, descrmine the empiniaal focmuli of the copper chlonde
