Chemical reactions involving the transfer of electrons from one reactant to another are called oxidation-reduction reactions or redox reactions. In a redox reaction, two half-reactions occur; one reactant gives up electrons (undergoes oxidation) and another reactant gains electrons (undergoes reduction). Voltaic cell is a device in which a redox reaction spontaneously occurs and produces an electric current. In order for the transfer of electrons in a redox reaction to produce an electric current and be useful, the electrons are made to pass through an external electrically conducting wire instead of being directly transferred between the oxidizing and reducing agents.
A salt bridge must be used to avoid polarization of the electrodes by facilitating the circulation of ions from electrolyte. Each electrode is connected to the voltmeter by clips and wires. The voltmeter measures the voltage generated by the redox reaction. The voltage reading will be positive when the electrodes are connected properly for spontaneous reaction. A redox reaction occurs when the species with higher reduction potential is connected as the cathode.
Research Question: What is the effect of different concentration of negative terminal electrolyte on the potential difference in voltaic cell?
Hypothesis: The lower the concentration of negative terminal electrolyte, the higher the potential difference in voltaic cell.
Manipulated variable| Concentration of negative terminal electrolyte * Use zinc sulphate solution, ZnSO4 as the negative terminal electrolyte throughout the experiment * Use zinc sulphate solution, ZnSO4 of different concentration, 1.0M, 0.10M, 0.010M and 0.0010M * Measure 40g, 4g, 0.4g and 0.04g of zinc sulphate powder then mix it in distilled water respectively until all the salt are completely dissolves then pour the solution into volumetric flask and add water until it make up to 250ml.
| Responding variable| Potential difference * Measure the potential difference with a voltmeter * Take readings of potential difference when using different concentration of zinc sulphate solution, ZnSO4| Fixed variable| Type of electrode * Use two electrodes of different type, copper and zinc * Use electrodes of the same size, 5cm x 1cmPositive terminal electrolyte * Use copper (II) sulphate solution, CuSO4 as the positive terminal electrolyte * Use the same concentration of 1.0M copper (II) sulphate solution, CuSO4 throughout the experimentType of salt bridge * Use the same type of salt bridge, NaNO3 throughout the experiment.|
Copper (II) sulphate solution, CuSO4
5cm x 1cm copper sheet electrode
Voltmeter
5cm x 1cm zinc sheet electrode
Cotton string soaked with sodium nitrate, NaNO3
Zinc sulphate solution, ZnSO4
Copper (II) sulphate solution, CuSO4
5cm x 1cm copper sheet electrode
Voltmeter
5cm x 1cm zinc sheet electrode
Cotton string soaked with sodium nitrate, NaNO3
Zinc sulphate solution, ZnSO4
Weight out 40.00g, 4.00g, 0.40g and 0.04g of zinc sulphate powder then dissolve the powder into distilled water in 50ml beaker respectively. 2. Pour the zinc sulphate solution into 250ml volumetric flask saperately and label it. 3. Add distilled water into each volumetric flask until it makes up to 250ml. 4. Mix the solution well in each volumetric flask.
Weight out 100g of sodium nitrate powder then dissolves the powder into distilled water in 50ml beaker. 6. Pour the sodium nitrate solution into 250ml volumetric flask then add distilled water until it makes up to 250ml. Mix the solution well. 7. Pour the solution into 500ml beaker then soak 15cm cotton string in the sodium nitrate solution.
Weight out 40g of copper (II) sulphate powder then dissolves it into distilled water in 50ml beaker respectively. 9. Pour the copper (II) sulphate solution into 250ml volumetric flask then add distilled water until it makes up to 250ml. Mix the solution well.
Rinse the beaker and zinc rod with distilled water before adding zinc sulphate electrolyte of different concentration. Gently blot the zinc electrode and beaker with paper towel before adding zinc sulphate electrolyte of different concentration. Ensure that the cotton is properly soaked and absorbed the sodium nitrate solution, NaNO3. Avoid contacting the skin and eyes with chemicals.
Remember! This is just a sample.
You can get a custom paper by one of our expert writers.
Get your custom essay
Helping students since 2015
Essay Writing Service Features
Our Experience
No matter how complex your assignment is, we can find the right professional for your specific task. Contact Essay is an essay writing company that hires only the smartest minds to help you with your projects. Our expertise allows us to provide students with high-quality academic writing, editing & proofreading services.
Free Features
Free revision policy
$10Free bibliography & reference
$8Free title page
$8Free formatting
$8How Our Essay Writing Service Works
First, you will need to complete an order form. It's not difficult but, in case there is anything you find not to be clear, you may always call us so that we can guide you through it. On the order form, you will need to include some basic information concerning your order: subject, topic, number of pages, etc. We also encourage our clients to upload any relevant information or sources that will help.
Complete the order form
Once we have all the information and instructions that we need, we select the most suitable writer for your assignment. While everything seems to be clear, the writer, who has complete knowledge of the subject, may need clarification from you. It is at that point that you would receive a call or email from us.
Writer’s assignment
As soon as the writer has finished, it will be delivered both to the website and to your email address so that you will not miss it. If your deadline is close at hand, we will place a call to you to make sure that you receive the paper on time.
Completing the order and download