Available online
Description
Energy transfer following the collision of atoms and molecules in the gas phase can be calculated by a computer, and presented in the form of slow motion animated film. Such film makes a valuable c...ontribution to a students understanding of the parameters which determine, whether or not, chemical reaction will occur. In the programme Dr. Harding asks the student to compare seven different events, following collisions between an atom and a linear diatomic or triatomic molecule. Repeating the film sequences Dr. Harding interprets the energy transfer, and draws analogies to experiments with coupled pendulums and vibrating spring models. In the remaining part of the programme, Dr. Ross demonstrates the reaction between hydrogen and chlorine, and discusses a mechanism for this reaction, based on the different types of collision which take place when the reaction is initiated by light.
Energy transfer following the collision of atoms and molecules in the gas phase can be calculated by a computer, and presented in the form of slow motion animated film. Such film makes a valuable c...ontribution to a students understanding of the parameters which determine, whether or not, chemical reaction will occur. In the programme Dr. Harding asks the student to compare seven different events, following collisions between an atom and a linear diatomic or triatomic molecule. Repeating the film sequences Dr. Harding interprets the energy transfer, and draws analogies to experiments with coupled pendulums and vibrating spring models. In the remaining part of the programme, Dr. Ross demonstrates the reaction between hydrogen and chlorine, and discusses a mechanism for this reaction, based on the different types of collision which take place when the reaction is initiated by light.
| Module code and title: | ST285, "Solids, liquids and gases" |
|---|---|
| Item code: | ST285; 06 |
| First transmission date: | 14-04-1972 |
| Published: | 1972 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:14 |
| + Show more... | |
| Producer: | David Jackson |
| Contributors: | Charles Harding; Robert Ross |
| Publisher: | BBC Open University |
| Keyword(s): | Analogies; Animated film; Chlorine; Collision of atoms and molecules; Coupled pendulums; Gas phase; Hydrogen; Linear diatomic molecule; Triatomic molecule; Vibrating spring models |
| Footage description: | Charlie Harding introduces the programme. He simulates energy transfer in tri-atomic molecules with two swinging pendulums. Harding next demonstrates a more sophisticated simulation of a tri atomic molecule using a ball and spring model. He points out the value of models for studying chemical reactions and explains the sorts of measurements which can be taken from these models. Film of a computer simulation showing a vibrating triatomic molecule in collision with an atom. Short comment by Harding, then film continues. The chemical bonds of the triatomic molecule are seen to break. A second collision is simulated. This time the molecular bonds are preserved. The second collision de activates the molecule. Harding considers the formula products. Shots of a ball and spring simulation of a poly atomic molecule (six atoms). Harding sets one of the atoms in motion and the energy is transferred to the rest. He demonstrates that size of the molecules is a factor in its reactivity. Shots of a computer simulation of an atom in collision with a diatomic molecule. The molecular bond is broken and a new bond formed with the atom. Shots of a computer simulation of an atom in collision with a tri-atomic molecule. The bond again breaks and new bonds are formed to make two di-atomic molecules. The same collision is shown again. This time the old bond holds and no new bonds are formed. Shots of a computer simulation of a diatomic molecule in collision with an atom. The equation is derived. Shots of a computer simulation of triatomic molecules in collision with atoms. The equation is derived. Commentary points out that molecular complexity affects the rate of reaction. Shots of a computer simulation of a triatomic molecule in collision with an atom. This time the equation Products? results. Harding sums up the programme so far. Well, we've come. Computer simulation of an atom colliding with a diatomic molecule at an angle of 9O degrees to the molecule's axis. No reaction occurs. The simulation then shows the collision along the axis and this time a reaction does occur. The simulation is run again. R.A. Ross examines the reaction. Shots of a computer simulation showing the collision of chlorine molecules. Another simulation shows the breaking of the chlorine bond by light rather than collision with another molecule. Shots of a computer simulation showing chlorine atoms in collision with hydrogen molecules and then a hydrogen atom colliding with a chlorine molecule. Shot of an animated graph showing the energy barrier for the H2 + Cl2 reaction. Ross reacts Ho with CI2 in the laboratory. He explains the experimental set up and then bombards the mixture with light. This initiates the reaction. Ross explains what has happened during the reaction. He uses a caption board with the chemical equations for the reaction as an aid. |
| Master spool number: | 6HT/70812 |
| Production number: | 00525_1030 |
| Videofinder number: | 683 |
| Available to public: | no |
