ChemCollective-Virtual-Labs/C3/Metal-Displacement-Reactions/English-timed

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Time Narration
00:01 Welcome to this spoken tutorial on Metal Displacement Reactions using Vlabs.
00:07 In this tutorial we will learn to, Carry out displacement reactions of,

Magnesium

Zinc

Lead

Copper and

Silver

00:20 Arrange metals in decreasing order of reactivity.
00:24 To follow this tutorial you should be familiar with, ChemCollective Vlabs interface.
00:31 If not for relevant tutorials, please visit our website.
00:37 Here I am using

Mac OS version 10.10.5

ChemCollective Vlabs version 2.1.0

Java version 8.

00:51 Here I have opened Virtual Chemistry Labs application window.

Default lab setup window opens.

01:01 Click on File menu and select Load Homework option.
01:06 Default Lab Setup dialog box opens.
01:10 Double-Click on Redox Folder.

Then double-Click on Redox Reaction Series.

01:18 Click on Problem Description in the Stockroom Explorer.
01:23 The problem states that, Perform metal displacement reactions.
01:29 Arrange the given metals from strongest to weakest reducing agent.
01:35 Stockroom Explorer is provided with all the required metals and their salt solutions.
01:43 Let us define Redox Reactions.

An oxidation-reduction (redox) reaction, involves transfer of electrons between two species.

01:54 Oxidation is loss of electrons by any species.

Reduction is gain of electrons by any species.

02:04 Metal displacement reactions are a type of Redox reactions.
02:09 In metal displacement reactions, a more reactive metal displaces a less reactive metal in a metal salt solution.
02:19 This slide shows the activity series of some metals used in displacement reactions.
02:27 Here is an example of metal displacement reaction.
02:32 Silver ions in silver nitrate can be replaced by copper to form copper nitrate.
02:39 Elemental silver is precipitated in the reaction.

Silver has lower oxidation potential than copper. It cannot replace copper from copper nitrate.

02:54 Switch to application window

Click on Workbench1.

03:00 Right-click on the workbench tab to rename.

Type name as Magnesium-rxn (Magnesium reaction).

03:08 Let us now demonstrate the reactivity of Magnesium metal.
03:13 From the Stockroom Explorer, click on Solids cabinet, double-click on Magnesium.
03:21 Click on Solutions cabinet, double-click on,

0.1 M Copper nitrate

0.1 M Zinc Nitrate

0.1 M Lead Nitrate

0.2 M Silver Nitrate.

03:37 Close the cabinets.
03:40 Click on Glassware menu, and select 250 mL Erlenmeyer flask
03:46 We need 4 flasks for this experiment.

Make duplicates of the Erlenmeyer flask.

03:55 Rename the flasks with corresponding metal symbols, Zinc, Lead , Silver and Copper.
04:06 Arrange the apparatus and chemicals.

Click on any one of the bottles containing solution.

04:14 The Solution Info panel shows the bottle contains 50 ml of solution.
04:21 Pour the contents of the bottles into respective flasks using Precise transfer mode.
04:28 Type 50 in the Transfer amount input bar.

Click on Pour.

04:35 Similarly transfer contents of the bottles into flasks.
04:44 Keep the empty bottles aside.
04:48 Click on each Erlenmeyer flask and note the concentration of the metal ions.
04:57 Pour 1 gram of solid Magnesium metal in each flask using Precise transfer mode.
05:11 Click on the flask containing copper nitrate .

Observe that green color of the solution has disappeared.

05:20 Temperature increases on addition, then decreases.

The reaction is Exothermic.

05:28 In the Solution Info Panel, concentration of copper ions is zero.
05:34 Magnesium ions are observed in the solution.

This means that Magnesium has displaced copper ions from the solution.

05:44 Click on Solid radio button.

Observe that metallic copper is now deposited in the solution.

05:52 This is because Magnesium has higher oxidation potential than copper.
05:58 Click on the flask containing Zinc nitrate.
06:02 Click on Aqueous radio button on the Solution Info Panel.

Concentration of Zinc ions is zero.

06:11 Magnesium ions are now observed.

Click on Solid radio button.

06:18 Observe that Zinc is now found in the solution.
06:22 Magnesium has replaced Zinc ions from its solution.
06:27 Click on the flask containing lead nitrate.

Observe Solution Info panel.

06:35 Magnesium has replaced Lead ions from its solution.
06:45 Click on the flask containing silver nitrate.

Observe Solution Info panel.

06:51 Magnesium has replaced Silver ions from its solution.
06:59 Now let us demonstrate the activity of Zinc.

Click on File menu and select New Workbench.

07:08 Rename the workbench as Zinc-reaction.
07:12 From Solids cabinet select Zinc.
07:16 Click on Solutions cabinet and select

0.1 M Copper Nitrate

0.1 M Magnesium Nitrate

0.1 M Lead Nitrate

0.2 M Silver Nitrate

07:30 Close the cabinets.
07:33 As we did in the previous experiment, take 4 Erlenmeyer flasks.
07:39 Rename the flasks with corresponding metal symbols Magnesium, Lead, Copper and Silver.

Arrange the apparatus.

07:53 Pour the contents of the bottles into the respective flasks.

Type 50 in the Transfer amount input bar.

Click on Pour.

08:12 Pour 1 g of solid Zinc metal in each flask.
08:17 Type 1 in the Transfer amount input bar.

Click on Pour.

08:29 Click on the flask containing copper nitrate.
08:33 Observe that Copper is displaced by Zinc.
08:38 Click on the flask containing Magnesium nitrate.
08:42 Zinc cannot replace Magnesium from the solution.

Because Zinc has lower oxidation potential than Magnesium.

08:51 Hence, there is no reaction and Zinc remains in the solution.
08:57 Similarly click on flasks containing Lead nitrate and Silver nitrate.

Observe that Zinc displaces both Lead and Silver.

09:10 Similarly perform the experiments for Lead, Copper and Silver.

Open a different workbench for each metal displacement reaction.

09:23 Rename the workbenches as Lead-reaction, Copper-reaction and Silver-reaction.
09:31 Required metals and salt solutions are available in the Stockroom Explorer.
09:38 We have performed these experiments.
09:47 Here are the observations.
09:50 We have tabulated the results as shown.

Magnesium has higher oxidation potential value.

09:58 Magnesium displaces metal ions, Zinc, lead, Copper and silver which have lower oxidation potentials.
10:09 Silver with lowest oxidation potential cannot displace,

Magnesium, zinc, lead or copper ions from solution.

10:19 The order of reactivity from strongest to weakest reducing agents is as follows.
10:27 Let us summarize

In this tutorial we have, Determined the order of reactivity for the following metals,

Magnesium

Zinc

Lead

Copper and

Silver.

10:41 As an assignment, Perform displacement reactions using solutions of metal halides.
10:49 Establish the order of reactivity of halogens.
10:53 The required chemicals are available in the Stockroom Explorer.
10:58 The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it.

11:05 The Spoken Tutorial Project team, conducts workshops using spoken tutorials and

gives certificates on passing online tests.

For more details, please write to us.

11:17 Please post your timed queries in this forum.
11:21 Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

More information on this mission is available at this link.

11:32 This tutorial is contributed by Snehalatha Kaliappan and Madhuri Ganapathi from IIT-Bombay. Thank you for joining.

Contributors and Content Editors

PoojaMoolya