• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Determine the formula of the hydrate in hydrated copper (II) sulfate empirically, i.e. to find x in the formula: (CuSO4 · xH2O) and thus ascertain the degree of hydration.

Extracts from this document...

Introduction

IB Chemistry - Practical Report Name: Chris Bolton Partner: Jamie Gearing Date(s) Conducted: 14/05/04 Topic: Stoichiometry Experiment: The Degree of Hydration of Copper (II) Sulfate, CuSO4 � xH2O Aim: To determine the formula of the hydrate in hydrated copper (II) sulfate empirically, i.e. to find x in the formula: (CuSO4 � xH2O) and thus ascertain the degree of hydration. Apparatus: MATERIALS: Hydrated copper (II) sufate GENERAL: Heatproof mat, tripod, Bunsen burner, pipeclay triangle, crucible, metal tongs, glass mixing rod, spatula, electronic balance SAFETY: Lab coat and safety glasses to be worn at all times Method: Refer to attached worksheet for given method AMMENDMENTS/ADDITIONS/SAFETY PRECAUTIONS: * If required, manipulate CuSO4 � xH2O with glass rod during heating to assist process * Ensure that heating is gentle (as indicated) to avoid either damage to the crucible or overheating the sample (this could result in impurities in the anhydrous compound) * Ensure to control Bunsen flame to avoid blackening pipeclay triangle or crucible Results: Fig. 1 A Table to Show Key Masses COMPONENTS MASS (g) |ERROR|(g) Crucible 8.024 ? 0.002 Crucible and CuSO4 � xH2O 10.058 ? 0.002 NOTE: Systematic error associated with electronic balance is consistently ? 0.002 g Initial observations of hydrated copper (II) sulfate: Blue crystalline solid Fig. ...read more.

Middle

mol ? 0.00794/0.00794 mol : ? 0.0426mol/0.00794mol 1 : ? 5.36 So both the exact and the approximate ratio has been determined. However, presumably due to experimental errors the ratio is, of course, not a perfect integer. This can be dealt with in two ways: a) the ratio of 1 : ? 5.36 can be rounded to a ratio of 1 : 5 (which gives the formula of the hydrate as 5H2O) - but since 5.36 does not closely approximate 5.00, this is not an appropriate assumption. b) Alternately, a smaller rounding gives a ratio of 1 : 5.4 and this ratio can be easily multiplied to give an integer ratio as such: 5 x (1 : 5.4) = 5 : 27 which is simply a ratio, the derivation of which required fewer assumptions than the simpler ration of 1 : 5. Hence the empirical formula has been determined as follows: Ideally* Experimentally CuSO4 : xH2O CuSO4 : xH2O 1 : 5 5 : 27 CuSO4 � 5H2O 5CuSO4 � 27H2O *NOTE: this formula has been included for the purpose of discussion So according to experimentation, the degree of hydration in hydrated copper (II) sulfate is 5 : 27 (27H2O) - that is to say, for every five moles of copper (II) ...read more.

Conclusion

These uncertainties have been included in calculations above without working. It is likely that a culmination of these errors - with an emphasis on burning the sample - resulted in a degree of imprecision in these results. Regardless, the results were still quite conclusive. Improvements: Several aspects of this experiment could be developed to yield more accurate and precise results. The influence of random and systematic errors in this experiment was probably of less consequence than the overheating of the sample which, while minor, would have had an effect on the mass of the sample. The key improvement to this experiment would therefore be to decrease the intensity with which flame is applied to the crucible. This would be to reduce the possibility of overheating, and increase the period of time spent dehydrating the sample to ensure a slower, more thorough (i.e. ensuring that most of the sample is anhydrous) and less intense dehydration. This improvement would allow a more thorough development of the sample, and more frequent processing on the scales. In addition to this, either repetition of the experiment to obtain a broader spread of results or a collation of class results may have yielded more accurate results, as the mean of the results would probably have given a ratio for hydrated copper (II) sulfate much closer the accepted literature value of 1 : 5, or CuSO4 � 5H2O. Chris Bolton ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Classifying Materials section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Classifying Materials essays

  1. Determine BaCl2.2 H2O -Gravimetric Analysis Lab

    - 28.38 � 0.01g (Mass of Crucible, Lid and Heated Barium Chloride after 2nd heating) = 0.27 � 0.02g (Mass of water removed from Barium Chloride on 2nd Heating) Mass of Water Removed from Barium Chloride on 3rd Heating: 28.65 � 0.01g (Mass of Crucible and Lid and Barium Chloride Sample)

  2. Investigation to Identify the Formula of Hydrated Copper Sulphate and in doing so Find ...

    Find formulas. AMMENDMENTS/ADDITIONS/SAFETY PRECAUTIONS: * If required, manipulate CuSO4 � xH2O with glass rod during heating to assist process. * Ensure that heating is gentle (as indicated) to avoid either damage to the crucible or overheating the sample (this could result in impurities in the anhydrous compound).

  1. Our experiment consisted of two samples of water containing unknown substances, and our objective ...

    Then add some silver nitrate to it (in effect you've added AgNO3) and a precipitate forms. A chloride produces a white precipitate of silver chloride, a bromide a cream precipitate of silver bromide and an iodide a yellow precipitate of silver iodide.

  2. Gold. For thousands of years, gold has been regarded as the finest and ...

    I think my results could have been more reliable if I'd asked more people, and also if I'd asked people from other streets, as these results may not have applied to everyone. These are the questions I used: 1. Do you own gold jewellery?

  1. Enthalpy of Hydration Lab

    y= .0003x + 21.615 y final=31.07 ?T = 9.35 y = .0008x +31.64 yintial= 21.71 Q= -(9.35)(3.84 J g-1 C-1) (103.49 g) = -3715 J Moles = .0777 ?H2= These steps were taken to calculate the for all four of the trials and the average of the anhydrous as well

  2. Relationship between mass of MgO and its formula

    Safety - Use tongs to hold the crucible, as it will be very hot coming from the Bunsen burner - Wear goggles at all times during the experiment - Always stand up during the experiment - Weigh the crucible after it has cooled down after the experiment Fair test Always

  1. material science unit 2 task 2

    Self-lubricating bearings. 10. Magnetic items like tapes or hard disks like floppy disks. 11. Optical wave-guides. 12. Night-vision 13. High dielectric constant. 14. Gas laser tubes. Ballistic armor. Test tubes and beakers, elbow liners. 15. welding system Examples of oxides that make up ceramics: Silicon dioxide, aluminium oxide, iron oxide etc...

  2. Determination of the formula of hydrated iron sulphate

    +16 Moles of H2O = 0.0362 correct to 3 significant figures To calculate the formula of FeSO4. xH2O the smallest number of the two values for the moles of FeSO4 and H2O needs to be made to 1 and the ratio then calculated.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work