Available online
Description
The programme employs interesting demonstrations and a specifically designed game to teach some different concepts of chemical equilibrium.
The programme employs interesting demonstrations and a specifically designed game to teach some different concepts of chemical equilibrium.
| Module code and title: | S101, Science: a foundation course |
|---|---|
| Item code: | S101; 14 |
| First transmission date: | 05-06-1979 |
| Published: | 1979 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:00 |
| + Show more... | |
| Producer: | David Jackson |
| Contributors: | Ian Soutar; Kiki Warr |
| Publisher: | BBC Open University |
| Subject terms: | Chemical equilibrium; Chemistry, Inorganic |
| Footage description: | Ian Soutar and Kiki Warr introduce the program with with a party trick. Soutar pours a clear liquid into a decanter. The liquid immediately turns red. He then pours the red liquid from the decanter into two glasses. It remains red in one glass but turns clear in the other. To demonstrate that acids are dissociated into hydrogen ions in aqueous solution, Soutar and Kiki Warr test a sample of hydrochloric acid and one of acetic with a pH meter. Pointing to a blackboard which has on it the formulae of the above reactions, Kiki Warr explains that hydrochloric acid is fully dissociated in solution where acetic acid is only partially dissociated and that when acetic acid is in aqueous solution, an equilibrium is established between undissociated acid and association products. In order to illustrate the principles of chemical equilibrium, Kiki Warr and Ian Soutar play a specially designed board game. Ian Soutar dissolves some sodium acetate in water and adds this to a solution of acetic acid. He tests the results with a pH meter and compares them with the results of earlier tests on acetic acid solution alone. Kiki Warr examines the equation for this reaction and points out that the equilibrium has been shifted. Warr and Soutar go on to show how the ideas on chemical equilibrium from the game above can be used to explain the party trick at the beginning. Kiki Warr and then Ian Soutar discuss the concept of equilibrium constant. Soutar demonstrates a machine, an absorption spectrometer, which is used as the basis for measuring the equilibrium constant. Shots of the visible spectrum of a liquid and also a graphic representation of the spectrum. Writing on a pad of paper and looking at graphic spectra from the solutions tested by the machine above, Soutar shows how the equilibrium constant can be manipulated. Kiki Varr sums up the programme. Ian Soutar does one final demonstration. He takes an equilibrium mixture of two gases, N2O4 and NO2 and applies heat. He compares this with a cold mixture and asks students to interpret the results. |
| Master spool number: | 6HT/73096 |
| Production number: | FOUS014S |
| Videofinder number: | 1189 |
| Available to public: | no |
