Empirical Formula Of Copper

Topics: Chemistry, Hydrogen, Aluminium Pages: 10 (1825 words) Published: February 3, 2015


Empirical Formula of Copper (II) Chloride
Gabriella Jane Lukas
B1401404

HELP University
Empirical Formula of Copper (II) Chloride

Objectives
1. To validate that the empirical formula of copper (II) chloride is . 2. To calculate the percent composition of copper in copper (II) chloride. 3. To illustrate the Law of Constant Composition in copper (II) chloride. 4. To study the reaction between copper (II) chloride solution and aluminium metal.

Introduction
One of the most fundamental statements of the atomic theory is that elements combine in simple whole number ratios. This observation gives support to the theory of atoms, since no one would expect atoms to combine. It is observed that the combining ratio for a given compound is constant regardless of the origin of the pure substance. This is known as the Law of constant composition. The mass contribution of each atom in a compound is a function of the number of atoms in the simplest formula and the relative mass of each atom. The mass contribution is usually referred as the percent composition of a compound (“Determination of”, n.d., p. 1). An empirical formula of a compound provides a number of information. It gives the simplest whole-number ratio between the numbers of atoms of all the elements present in the compound, as well as the names of all the elements present in the compound (“The significance,”, n.d., Significance section, para. 1). In this experiment, the empirical formula of a compound consisting copper and chlorine will be verified as . A known mass of aluminium metal is added to a carefully measured volume of blue solution known to contain a certain amount of copper (II) chloride. As the reaction proceeds, the blue colour of the solution will disappear and a reddish solid of copper metal will appear. Once the reaction is complete, the copper metal is left to dry and weighed together with the excess aluminium. Knowing the original mass of copper (II) chloride present, the empirical formula can be determined.

Materials
1. 1. 1 g of copper (II) chloride
2. 2. 60 ml of distilled water
3. Aluminium wire
3. 4. Electronic balance
4. 5. Pasteur pipette
5. 6. Buchner funnel
6. 7. Filter paper
7. 8. Forceps
8. 9. Glass rod
9. 10. Weighing container
10. 11. Watch glass
11. 12. Acetone
12.
13. Method
14. 1. 1 gram of copper (II) chloride is weighed on an electronic balance using a container. The weight of the solid is recorded. 15. 2. The copper (II) chloride is transferred to a 100 ml beaker and 60 ml of distilled water is added. The contents in the beaker are stirred with a glass rod until the solid is completely dissolved. 16. 3. A handle is made on one end of a 12.5 cm length of aluminium wire, and a flat coil on the other end. The wire is hung at the side of the beaker, immersing the coil in the solution. 17. 4. The wire is shaken when flakes of brown copper are seen accumulating on the wire until the initial blue colour of the copper (II) ions disappear. 18. 5. A vacuum filtration is set up using a Buchner funnel. 19. 6. A filter paper that fits into the funnel is weighed. The weight of the filter paper is recorded. 7. The filter paper is moistened with distilled water and the water aspirator is turned on. 8. The copper is filtered through the Buchner funnel. Finally, the copper is washed in the funnel with 30 ml of acetone. The copper is left on the filter paper for 10 minutes with the water running. 20. 9. Using a pair of forceps, the filter paper is carefully removed from the Buchner funnel. The filter paper and the copper are weighed and recorded. 21. 10. The weight of chlorine is obtained by subtraction.

22. 11. The empirical formula of copper (II) chloride and the error in determining the percentage of copper is determined. 23.
24. Results
25. Table 1
26. Data for Copper (II) Chloride Analysis
27. Weight of copper (II) chloride
28. 1.01 g
29. Weight of filter paper
30. 0.21 g
31. Weight of watch...

References: 92. Determination of a chemical formula. (2010). Retrieved from http://www.msu.edu/~sparksb1/apchem/Sample_Lab_1.doc
93. Determination of empirical formula. (n.d.). Retrieved from http://mhchem.org/221/pdfLabs221/EmpiricalFormula.pdf
94. Observing chemical changes. (2008). Retrieved from http://wikieducator.org/Chemistry/Observing_Chemical_Changes_Marking_Scheme
95. Sass, A. (n.d.). Aluminium burner. Retrieved from http://www.elmhurst.edu/~chm/demos/aluminumburner2.htm
96. The significance of an empirical formula. (n.d.). Retrieved from http://www.preservearticles.com/201012281824/empirical-formula-significance.html
97. What do copper (II) chloride and aluminium form when they are combined. (n.d.). Retrieved from http://www.ask.com/science/copper-ii-chloride-aluminum-form-combined-18eb9c5296e60c57/
98.
99.
Continue Reading

Please join StudyMode to read the full document

You May Also Find These Documents Helpful

  • Essay about Percent Copper and Formula of a Copper Compound
  • Empirical Formula : Lab Report Essay
  • Empirical Formula of Copper Sulfate (Incomplete) Essay
  • Essay on Determining the Empirical Formula of Magnesium Oxide
  • Empirical Formula PRE LAB Essay
  • Empirical Formula of Magnesium Oxide Essay
  • Empirical Formula Lab Report Essay
  • Empirical Formula of Magnesium Oxide Essay

Become a StudyMode Member

Sign Up - It's Free
--Czasopisma | Kaspersky Internet Security 2019 1 PC 2 Years - Windows License | IMDb: 7 HD A Fat Wreck