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

Investigate the factors, which could affect the current flowing during electrolysis of Sodium Chloride (Salt).

Extracts from this document...

Introduction

-  - Electrolysis Investigation -Laura Evans 10sa

Electrolysis Investigation

Task

Investigate the factors, which could affect the current flowing during electrolysis of Sodium Chloride (Salt).

Introduction

The factors that could affect the current flowing during the electrolysis of Sodium Chloride are:

  • Temperature
  • Concentration
  • Distance between electrodes
  • Surface area of cathode/anode in solution
  • Voltage in the circuit
  • Resistors in the circuit.

 I am going to investigate how the concentration of Sodium Chloride in the solution affects the current flowing. I predict that as the concentration goes up, the current will also increase because there are more sodium and chloride ions to carry their charge to the electrodes therefore increasing the current. The definition of an electrolyte is ‘a compound that doesn’t conduct electricity when solid, but does conduct when molten or dissolved in water’. I think that the more of the electrolytes you have, the greater the current.

   In a solution of Sodium Chloride, 4 ions are present; sodium Na+, hydrogen H+, chloride Cl- and hydroxide OH-. The H+ and Cl- ions are discharged at the electrodes. Hydrogen comes off at the cathode (-). This is the half-equation showing what happens at the cathode:

...read more.

Middle

Taking the range of 8 readings 4 times.

One of the safety precautions I will take is to make sure that I wear safety glasses while doing the experiment.

Preliminary Work

I decided that, to get an idea of what kind of results I was aiming to get from my main investigation and to identify any problems I might encounter, I performed roughly the same experiment as described above, I set the equipment up as shown below:

The major difference between the main investigation and my preliminary work was that I measured out the amount of salt for the solution by spatulas. I measured the current with 0-12 spatulas of salt dissolved in distilled water. From this I decided that measuring by mass was more accurate, but here I only wanted to get a rough idea. The results of my preliminary work are shown below:

Amount of Sodium Chloride (spatulas)

Current (Amps)

0 (distilled water)

0.00

2

0.23

4

0.33

6

0.50

8

0.59

10

0.64

12

0.70

Method

I performed the experiment as outlined in the plan. Because in my preliminary work, I had already highlighted and found solutions for any possible problems, I did not encounter any during the final investigation.

...read more.

Conclusion

Conclusion

From my graph, it is clear that the results increase in a curve.  Trials 1 and 4 are generally above average and trials 2 and 3 are generally below average. My results for 8g of sodium chloride appear to be anomalous, as they don’t fit into the curve. My results from my preliminary also indicate that the results should form a curve. My prediction is supported by my results because as the concentration increases, so does the current. My results also show that the increase in current between 0g and 2g of salt is substantially greater than the difference in current between 12g and 14g of salt. This would suggest that the solution is becoming saturated and more full of sodium and chloride ions, so the increase is reduced.  

Evaluation

I think that my experiment was very effective and I proved my prediction to be true. Although I had some anomalous results, the general trend in my results was clear. The test could have been fairer if I had used the same distilled water for each trial, and just added 2g of salt for each level. I would like to try the experiment using the same water for each trial, to see whether it makes any difference.

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Electrical & Thermal Physics 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 AS and A Level Electrical & Thermal Physics essays

  1. Assess how changing the electric current in the electrolysis of acidified water affects the ...

    gas produced by the total number of minutes that the experiment runs for (2). Current (A) Gas volume/2 (rate of H2 production per min) In order to ensure a fair and accurate test, it is necessary to make sure that the current is the only variable.

  2. The electrolysis of copper from copper sulphate solution

    I must ensure that I am wearing an apron or lab coat which will shield my clothes from any spills of the copper sulphate solution. 3. Just to be careful, I will mix the copper sulphate solution concentrations and measure them out next to or above a sink.

  1. How does the mass of copper plated in the electrolysis of copper sulphate solution ...

    First of all, I have the a small current to start of with and so I can use the results of this value and compare it with the larger value(1 amp) and see what the kind of affect a small current has on the mass changes of the electrodes.

  2. Resistance of electrolyte

    The further apart the electrodes are the higher the resistance will be. My graph confirms this. I can see that for every 1cm decrease in the distance between the electrodes the resistances decreases by an average of 0.9 ohms. Therefore my prediction was partially correct as the resistance did change in relation to the distance between the electrodes.

  1. Investigate one of the factors effecting current flowing through a wire.

    Accurate results are achievable when varying the length because we can fix accurately all other factors. It is also practical to investigate length because it is available as a continuous variable, whereas area and resistivity are discrete variables. I predict that the longer the length of wire, the higher the resistance and so the smaller the current in the wire.

  2. How does the length of a conductor affect the current flowing through it?

    Conductors A neutral atom has equal protons and neutrons but if you take away or add electrons it becomes what is known as an ion - a charged atom. Positively charged ions are called cations and negatively charged ions are called anions, the number of electrons in a neutral atom

  1. In this investigation, I will be looking at the resistance of a solution, and ...

    This will mean that it will have no affect on the resistance, which is affected by the salt concentration. Another thing which could affect the results, or change the experiment to show the results better, would be to use elements with a charge of 2+ and 2-, so that they will react.

  2. In this experiment we are investigating the effect of concentration on the current flowing ...

    Since each have opposing charges of 2 then they attract and form an ionic compound, copper sulphate. When the electrons are given up and received by the ions from the electrodes, there is a current created. The more ions in the solution, the more that will be pulled towards the

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