Chemistry Lab Report Water Hydration Introduction

Chemistry Lab Report piss Hyd symmetryn Int magnetic poleuction A render crystal or hydrated occurs when urine becomes tightly attracted to a metal sodium chloride base on its polarity. The water one thousand molculecules maintain integrity as molecules, however they are considered to be part of the formula of the hydrate. When the hydrate metal salt crystal is heated, the attractions to the water are broken by the heat energy and the water bilk from the crystal. After heating the salt crystal is called as anhydrous, which means without water. umpteen of the salt contain transition metals such as cobalt that is vivid (purple).Often the pretense of transition metal like cobalts color will transport as a function of how many irrigate it is attracted to. Compounds containing water ( urine) of hydrated are written with water separate by a dot (. ). This (. ) means for hydrated metal salt in that lieu are how many count of moles of water bound to each mole of that metal s alt. Research Question The aim of this experiment is to calculate the number of moles of water bounded to each mole of cobalt chloride ( CoCl2. piddle). This cobalt chloride hydrated whitethorn be monohydrate with 1 mole of water attracted to cobalt chloride.It may be dihydrate, trihydrate, tetrahydrate or pentahydrate your task is to determine which one you are endown. opening If cobalt chloride were heated until there is no further lose in heaviness, 6 moles of water would be lost from 1 mole of salt. thence it is predicted that there are 6 moles of water in this reaction. Materials (Apparatus) 1. 3 gram of cobalt chloride 2. Evaporating dish 3. Tongs to hold the evaporating dish 4. Ring bandstand 5. Iron ring 6. Clamp 7. bunsen burner 8. Matches 9. 40. 20 g coat of the melting pot 10. Digital chemical equilibrium/ g 0. 01 11.Clay triplicity 12. Gloss rod Procedure 1. Place an empty melting pot on digital balance by scruple of 0. 01g 2. Measure the size of the crucible without salt 3. give 3 gram of cobalt chloride to the crucible 4. Measure the total size of crucible containing cobalt chloride 5. Take the crucible containing salt, place it on the Bunsen burner by tongs. Place crucible on a clay triangle and iron ring to protect the crucible from falling. 6. Gently heat the crucible by Bunsen burner 7. Use a gloss rod to give a movement to cobalt chloride to crystalized. 8.Record time for salt crystallization 9. choke up heating when cobalt chloride crystalized 10. Wait for few second for crucible to cool down 11. Place and Measure the anhydrous crucible by digital balance 12. Using calculation find the number of moles in this reaction. CoCl2 . nH2O CoCl2 + nH2 Data Collection and Processing Process Observation during the experiment Changes in color As we started heating the crucible containing CoCl2. H2O , the color of the CoCl2 started to change from violet purple to dark purple and the blue in 6 minutes and it is because of water evaporatio n. Appearance of the salt during heating After 3 to 5 minutes, as water was evaporating and reaching its melting and boiling point, salt began to bubble. At the beginning of heating it was powdery solid then it changed to semiliquid and at last solid again. Volume of salt decreases because of lost of molecules. We waited for 10 minutes until it cooled down. Calculations Raw data collected Mass Grams Uncertainty /g 0. 01 Crucible 42. 20 g 0. 02 % Pure H2O 1. 36 g 0. 73 % Pure CoCl2 1. 66 g 0. 60 % Total uncertainty 0. 08 %Find the masses Crucible + CoCl2. H2O = 45. 23 g anhydrous = 43. 86 g Mass of pure H2O = 45. 23 43. 28 = 1. 36 g Mass of pure CoCl2 = 3. 02 1. 36 = 1. 66 g Find the uncertainty CoCl2 = 1. 66 = 0. 01 = 0. 60 % coulomb x H2O = 1. 36 = 0. 01 = 0. 73 % deoxycytidine monophosphate x Crucible = 42. 20 = 0. 01 = 0. 02 % 100 x Total uncertainty 0. 02 % + 0. 60 % + 0. 73 % = 1. 3 % 100 = 1. 3 = 0. 08 % 6 x Find the percentage of water % piddle = weight of wat er in precedent * 100 Original weight of sample % 45. 03 = 1. 36 *100 3. 02 Find the number of moles CoCl2 . H2O CoCl2 H2O 1. 661. 36 1. 66 * 18 n = 1. 36 * 130 29. 88 n = 176. 8 g 130 18 n n = 176. 8 / 29. 88 n = 6 moles CoCl2 . 6H2O CoCl2 +6H2O Conclusion From this experiment, I investigated that my system is fairly holy as I predicted. Therefore it is concluded that through empirical formula, the pointedness of hydration is hydrated CoCl2 was determined to a relative gunpoint of trueness. It is determined to be approximately 6 moles of water bonded with 1 mole of CoCl2 and giving CoCl2 . 6H2O. EvaluationOur experiment was fairly close as the ratio was 15. 9. However, the ratio achieved through this experiment was, while approximately accurate to the accepted literature value of 1 6, not so tiny tat this ratio could be assumed to anything greater or lesser than 1 significant figure. This anomaly can be explained by acknowledging slightly errors within the experimental proc ess. While the determined degree of hydration was not perfect, and therefore to find the current rather elaborate ratio a degree of rounding was still required, it was still reasonably accurate. Some errors can be 1.Over heating of the hydrated cobalt chloride can result in hot the anhydrous compound of cobalt chloride, therefore contaminating it with oxygen and alerting the mass present in the crucible. This could lead to varying degrees of inaccuracy. 2. Base on the fact that cobalt chloride is hydrophilic means it will absorb moisture from atmosphere. Therefore, the experiment should be conducted in a dry, well-aired lab to avoid as little absorption as possible. 3. In contrast to burning the anhydrous compound, the heating could have failed to completely remove all the water or revise it it may over heated that also effect on the accuracy.Improvements There are several ways to improve this experiment. The key emolument to this experiment would probably be to decrease the inte nsity with which flame is utilize to the crucible. This reduces the possibility to reduce overheating, and increase the period of time spent dehydrating the sample to ensure a slower, more through and less intense dehydration. another(prenominal) improvement can be using a lab, which has the suitable location for this experiment. At last, have a expert partner or instructor to tell u, when stop heating the crucible can improve the accuracy of constant mass to achieve.