ExpEYES/C2/Conductivity-of-ionic-solutions/English-timed

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Time Narration
00:01 Hello everyone.Welcome to this tutorial on Conductivity of ionic solutions.
00:07 In this tutorial we will learnt to:
  • Measure Conductivity and
  • Calculate the resistance of ionic solutions.
00:15 Here I am using,
  • ExpEYES version 3.1.0
  • Ubuntu Linux OS version 14.04
00:23 To follow this tutorial, you should be familiar with:

ExpEYES Junior interface. If not, for relevant tutorials, please visit our website.

00:35 Let's first define conductivity of a solution.
00:38 Conductivity of a solution is a measure of its ability to conduct electricity.
00:44 Conductivity of water is directly related to the concentration of ions dissolved in it.
00:51 Now we will demonstrate conductivity of tap water.
00:56 I will explain the circuit connections.A1 is connected to SINE.
01:02 Wires from SINE and A2 are dipped in glass tumbler containing tap water.
01:08 10K resistor is connected between A2 and GND.This is the circuit diagram.
01:16 Let's see the result on the Plot window.
01:20 On the Plot window, click on A1 and drag to CH1.A1 is assigned to CH1.
01:28 Click on A2, drag to CH2.

A2 is assigned to CH2.

01:35 Move the mSec/div slider to adjust the waves.Two sine waves are generated.
01:43 Black trace is the original sine wave.Red trace is conductivity of tap water.
01:50 Click on CH1 and drag to FIT.Click on CH2 and drag to FIT.
01:56 Observe the voltage and frequency values on the right side of the window.Notice that voltage of tap water is very less compared to the input voltage.
02:08 Right click on CH1 to see voltages and Phase difference in degree.
02:15 Now we will measure conductivity of copper sulphate solution.To make the solution one spatula of copper sulphate is dissolved in 100 ml of water.
02:27 In the same connection, wires from SINE and A2 are dipped in copper sulphate solution.
02:34 On the Plot window we can see the conductivity curve.
02:38 Red trace is conductivity of copper sulphate solution.
02:42 Increased conductivity of is due to copper and sulphate ions present in the solution.
02:48 Observe the voltage and frequency values on the right.
02:52 Right click on CH1 to see voltages and Phase difference values.
02:59 Now we will measure conductivity of dilute sulphuric acid solution.A few drops of dilute sulphuric acid are added to water.
03:09 Wires are dipped in sulphuric acid solution.Let's see the result on the Plot window.
03:17 Observe that black and red traces are almost coinciding with each other.
03:23 Conductivity of tap water has increased: on adding a few drops of dilute sulphuric acid.
03:30 Observe the voltage and frequency values on the right.
03:34 Right click on CH1 to see voltages and Phase difference in degree.
03:41 We will measure conductivity of dilute Potassium hydroxide solution.A few drops of dilute Potassium hydroxide solution are added to tap water.
03:52 We can see that black and red traces are almost coinciding with each other.
03:58 Notice the increased conductivity of:

tap water on adding a few drops of Potassium hydroxide solution.

04:05 Observe the voltage and frequency values on the right side of the window.
04:11 Right click on CH1 to see voltages and Phase difference in degree.
04:18 Using the voltage values we have calculated the resistance of ionic solutions and tabulated the results.
04:27 Resistance value for tap water is 7.7 KOhm

Resistance value for:

copper sulphate solution is 1.2 KOhm
04:38 sulphuric acid solution is 0.17 KOhm and * potassium hydroxide solution is 0.14 KOhm.

Notice that resistance values decreased with the increase in ionic concentration.

04:55 Let's summarize.
04:57 In this tutorial we have learnt to:
  • Measure Conductivity and
  • Calculate the resistance of ionic solutions
05:06 As an assignment,
  • Using sodium hydroxide, Acetic acid and sodium chloride solutions,
  • Measure conductivity and
  • Calculate the resistance of ionic solutions.
05:18 This video summarises the Spoken Tutorial project.If you do not have good bandwidth, you can download and watch it.
05:26 We conduct workshops using Spoken Tutorials and give certificates. Please contact us.
05:32 The Spoken Tutorial Project is funded by NMEICT, MHRD Government of India.
05:39 This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi. Thank you for joining.

Contributors and Content Editors

Pratik kamble, Sandhya.np14