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

Chemistry Lab Report- Determining the Enthalpy of Enthalpy Change, H, for a Redox Reaction (

Extracts from this document...


Chemistry Lab Report- Determining the Enthalpy of Enthalpy Change, ΔH, for a Redox Reaction (DCP, CE Criterion) Aim: The aim of this investigation is to experimentally determine the change in the enthalpy for the following redox (displacement) reaction: Zn (s) + Zn2+(aq) ---->+ Zn2++ Cu (s) Data Collection and Processing Recording Raw Data: Data Table: Time (seconds) (0.1 seconds) Temperature of Cu + Zn2+ Solution (°C) (±0.5°C) Trial 1 Temperature of Cu + Zn2+ Solution (°C) (±0.5°C) Trial 2 0 21 21 30 21 21 60 21 21 90 21 21 120 21 21 150 59 59 180 57 57 210 56 56 240 55 54 270 54 54 300 53 53 330 53 52 360 50 51 390 49 50 420 47 48 450 46 47 480 45 45 Minimum temperature of trial 1: 21 °C Maximum temperature for trial 1:59°C Temperature difference of trial 1: 38 °C Minimum temperature of trial 2: 21 °C Maximum temperature for trial 2:59 °C Temperature difference of trial 2: 38 °C Processing Raw Data: Mass of CuSO4 Solution (g) (±0.05g) Trial 1 25.0 grams Mass of Zinc Powder (g) (±0.05g) Trial 1 4.0 grams Mass of Copper Calorimeter (g) ...read more.


(±0.05g) + Mass of Zinc Powder (g) (±0.05g) Mass= 25.0g (±0.05g) +4.0g (±0.05g) Mass= 29.0g (±0.05g) Convert to Kg: 29.0g/1000= 0.0290Kg Mr= Cu-1; 63.55 x 1=63.55 S-1; 32.06 x 1=32.06 O-4 16.00 x 4=64.00 Total relative mass of = 63.55 + 32.06 + 64.00 Total relative mass of ethanol= 159.61= 159.6 (to 3 significant figures) Therefore; Number of Moles (Cu + Zn2+) = 29.0g/159.6 Number of Moles (Cu + Zn2+) = 0.1817 moles ΔH of combustion= ΔH /Number of moles ΔH of combustion= 4.6060.1817 moles= 25.34kJ Since this reaction is exothermic there is a negative sign in front of 25.34kJ,therefore ΔH= - 25.34kJ Propagating Error: Dealing with Errors: Analogue instrument: half of the smallest unit readable Digital instrument: the smallest unit readable Water in calorimeter was measured by a beaker first. Beaker: Analogue instrument- half of smallest measurement readable Half of 1 g = +_ 0.5g Multi meter measuring temperature: Digital instrument-smallest unit measurable = 1.0°C Weighting scale: Digital instrument-smallest unit measurable =0.1g %Uncertainty error of mass of Zn=(+_ 0.1g_4.0g) x 100% = 2.5% %Uncertainty error of mass of CuSO4 = (+_ 0.1g_25.0g) x 100% =0.4% Total %Uncertainty error of mass= %Uncertainty error of mass of Zn + %Uncertainty error of mass of CuSO4 Total %Uncertainty error of mass= 2.5% + 0.4%= 2.54% %Uncertainty error of temperature change of Cu + Zn2+ (1°C/ 38.0°C) ...read more.


Naturally, there are always uncertainties in the measuring devices we used; therefore, there is room for error for every measuring device used. However, this weakness is not major compared to the errors in relation to the calorimeter. S Human error: Some insignificant errors include; the transfer of copper sulphate solution from the 25ml beaker to the calorimeter where maybe not all the solution went to the calorimeter and some droplets could have been left behind in the 25ml beaker. Also, the transfer of the zinc powder from the weighing boat to the calorimeter; where some zinc powder might be left over on the weighing boat. Improving the experiment: The weaknesses and limitation suggest that there are improvements, which can be made to improve this experiment. For the closed system used, there was poor insulation for heat to not get lost. Therefore, a more sophisticated calorimeter with maximum insulation could prevent such heat loss. This could prevent energy to be transferred with the outside surroundings. Instead of using a beaker, we could use a pipette to measure the amount of copper sulphate to be used. Also, for the zinc transfer from the weighing boat to the calorimeter, we could use a more solidified zinc powder. The reason for this is that it will be easier for to transfer the zinc to the calorimeter with minimal zinc being left behind. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Chemistry 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 International Baccalaureate Chemistry essays

  1. The Enthalpy of Neutralization

    = 0.100mol H2O Calculating Enthalpy of Neutralization Mass/volume of solution [Mass = Volume, if we assume 1g = 1cm3] 25.00cm3 (� 0.5cm3) + 25.00cm3 (� 0.5cm3) = 50.00cm3 (� 1.0cm3) = 50.00g (� 1.0g) Calculation for measuring enthalpy changes [Q = m�c�?T] Q = (50.00g � 1.0g)

  2. Enthalpy of Combustion Lab Report

    This has been changed for each trial in order to provide more accuracy to the experiment. 3. The mass of the distilled water used in the experimental procedure is an independent variable. This has also been changed for each trial in order to provide a variety of results and cover all aspects of the experimental procedure.

  1. IB Chemistry - Boyle's Law Lab Report

    According to the formula, the pressure of a book had 251g/cm� (1440/5.73 = 251g/cm�). Therefore, the pressure will be constantly changed by the number of books. It is not the end of the pressure. I had to add the total pressure on the piston equals the pressure from the books plus the atmospheric pressure.

  2. IB Chemistry - Charles' Law Lab Report

    And then I need to change the Celsius into the Kelvin temperature because, the Lord Kelvin said that a reasonable temperature scale should start at a true zero value. Therefore, according to the results, when the temperature increased, the height (volume)

  1. Thermodynamics: Enthalpy of Neutralization and Calorimetry

    (17.715 �.001 g) (97.1 �.5 C�- 25.5 �.5 C�) = (1.00 cal/gC�) (69.133 �.001 g)(25.2 �.5 C�-21.7 �.5 C�) + (12.456 �.0351cal/C� )(25.2 �.5 C�- 21.7 �.5 C�) 97.1 �.5 C�- 25.5 �.5 C� 25.2 �.5 C�-21.7 �.5 C� 71.6 �.71 C� 3.5 �.71 C� (x cal/gC�) (17.715 �.001 g)

  2. Electrolysis of copper sulphate

    To find moles of electrons transferred. Moles of electrons =number of electronsAvogadro’s number â1.5 x10206.02 x 1023= 0.00099667774 moles e- 2. Reaction at the cathode: Cu2+ + 2e- â Cu ∴moles of Cu= moleselectrons2â 0.00024870466322= 0.00049833887 moles 1. To find Mass of Cu mass = moles x Molar Mass = 0.001243523316 x 63.5 = 0.032 g of Cu deposited (2.s.f)

  1. IA-Enthalpy Change of Reaction - Zinc and Copper Sulphate.

    The lid was made of thin plastic and was not airtight, so an easy pathway for heat loss was created. * A metallic stirring chip was used in this experiment and the temperature probe was submerged into the solution. Since only a small amount of chemicals was used, the chip

  2. Bomb calorimetry. The goal of this experiment was to use temperature data over ...

    was -5160 ± 20kJ/mol % error = |1-Experimental value/literature value|x100% = |1-(-4982.66)/(-5160)|x 100% = 3.44% Discussions This experiment was a success as each objective of the experiment was completed and the experimentally determined enthalpy of combustion of solid naphthalene was very close to its literature value.

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