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

In this investigation, I will be looking at the resistance of a solution, and the different things which affect it. In this experiment, I have chosen one variable, the salt concentration.

Extracts from this document...


Investigating the resistance of a solution

In this investigation, I will be looking at the resistance of a solution, and the different things which affect it. In this experiment, I have chosen one variable, the salt concentration. I have chosen the following variables for the concentration: in a beaker of 50ml (cm ) :        0 grams, 1,2,3,4 and 5 grams. Using the circuit shown below, I will find out the resistance of the salt solution. I will keep the following variables the same: I will keep the temperature at room temperature, by not changing the room temperature at all, by keeping windows shut, and not adjusting the radiators during the experiment. I will monitor the temperature, and make a note, just incase it changes. I will monitor the temperature using a thermometer, which will be placed into the beaker during each experiment. I will keep the voltage at 5V and 50cm  of solution, to keep it a fair test. The circuit will include a power pack, an ammeter, a voltmeter, two iron rods, a beaker, wires with crocodile clips and a measuring tube. I will repeat each experient once, so that I can find out an average, which will prevent anomolies affecting the graph, and incase there is a difference between the first attempt, and the second attempt, I will be able to spot the mistakes.


...read more.



Input Voltage

















This preliminary experiment showed me that I might have to use a higher voltage, because there would be a wider range of voltage readings, and this would make a graph more easy to read and understand. I believe that 7V would be a better input voltage to have, because it is not too high, and it is not to small, as it is a higher voltage used in my preliminary work.

        It shows me that 50cm  is enough water to use, because it will dissolve the amount of acid I plan to use, 5g of salt. It is important that it can dissolve into the solution, because when it comes to the point when no more salt can be dissolved into the solution, it affects the results, because adding more salt has no effect on the reisistance anymore.



Use for apparatus

Power pack

To supply the power


To connect the circuit


To measure the voltage


To measure the current


...read more.


I would set up the circuit, as shown in my plan. Before putting the solution in a beaker, into the circuit, and placing the rods into the solution, I will heat the beaker on a tripod over a bunsen, with a thermometer in the beaker. When the temperature inside the beaker has reached the required temperature for the experiment, I will remove it from the tripod, connect the circuit, and record results. I will then rince out the beaker, and repeat the experiment again to a different temperature each time, with different temperatures.

This would show whether temperature affects the rate or not, because in my experiment, the temperature remained constant.

        I could use different waters for my experiment. I used distilled water, as to not affect the results. If I was to use tapwater, I could monitor whether the particles within the tapwater affected the results or not, and whether they conduct electricity, and decrease the resistance.

        I believe that the experiment would be improved, if different solutions were formed, for example, using a different material to salt, to see if this would produce the same results in terms of results.

        I used a D.C supply, this was because I wanted to keep the particles at the same charge throughout the experiment, I could improve the experiment, by using an A.C current, to see if this affected the resistance.

        I could use a larger amount of water,because this would enable me to dissolve more salt into the solution, and therefore give a wider spread of results.

...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. Investigating the E.m.f and Internal Resistance of 2 cells on different circuit Structures.

    - The error percentage values of the resistors used could be incorrect and much higher than specified. This could increase or decrease the current depending on the value of the resistor. This therefore could either increase/decrease the current depending on the value of the resistor.

  2. Single Phase Transformer (Experiment) Report.

    These currents may be produced in a number of different ways, but a common method is to pass the anode current of a pentode through the primary winding of the scanning transformer with its secondary closed by a pair of deflecting coils.

  1. I am going to investigate what the resistivity is of a pencil lead. ...

    The Graph When drawing the line of best fit I have excluded the 1V point as I think that it is too far away from the line and would drastically change the resistance if I were to include it. The resistance of the pencil lead is the difference in y

  2. The aim of my investigation is to determine the specific heat capacity of aluminium.

    and it therefore takes less time for the heat to reach the desired location. Conduction can also occur in the liquid as long as there is a temperature difference. When two particles collide and one has more energy than the other does the particle with greater energy transfers some of

  1. Internal resistance investigation - I will conduct the following investigation with the aim to ...

    resistance of the variable resistor I have available) When I have collected all my results I will need to analyse them. To find the internal resistance I will draw a graph of Volts against Amps and plot the points that I have found. I will then join these up with a line of best fit and find the gradient.

  2. Find The Internal Resistance Of A Power Supply

    at minimum voltage setting of 2V to 0.45 ? at maximum voltage setting of 12V. These results especially show that there must be something wrong with my procedure which gives me a range of 10? which goes against my theory. These problems have been outlined below. Graph 1 Graph 2 Problems experienced with preliminary experiment: The results I obtained

  1. Investigating the monitoring systems used on modern day large A/C for detection of specific ...

    A warning light on the instrument panel is incorporated in the system to warn the pilot if an unacceptable level of vibration is reached, enabling the engine to be shut down and so reduce the risk of damage. FUEL QUANTITY The measurement of the quantity of fuel in the tanks

  2. Investigating how temperature affects the resistance in a wire

    So to stop this, the desired temperature in the water bath is kept constant with the monitoring of a thermometer and consequent adding of hot (from the kettle) or cold (from the tap) water. -Short-circuiting of the current supplied into the circuit, to stop any of the current being earthed

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