Reaction equation
2 CO + O2  2 CO2 |
This is the first of three formulas that give the name Three-Way Catalyst. It's what's called a reaction equation. Substances that react with each other are arranged to the left of the arrow, separated by a plus sign and
called 'reactants' or 'educts'. The desired result of the equation or experiment is to the right of the arrow and is called the product.
Whether the reaction works as stated above remains unclear until it is successful. Here, 2 molecules of CO (carbon monoxide) should react with oxygen and CO2 should result. The reaction equation indicates
both within the individual molecules by indices on the atoms and the number of molecules also by coefficients. In theory, one could let react a molecule of CO with an atom of O to form a molecule of CO2. But
that is not possible because oxygen is one of the seven elements (H2, O2, N2, F2, Cl2, Br2, I2) that do not occur individually, but
always in pairs.
| Educt side Product side |
| 2 CO + O2 2 CO2 |
You can see how to set up such an equation in the video below. It is important that the factors applicable to the entire molecule multiplied by the indices on both sides result in equal numbers of each atom and their valency
is taken into account. Oxygen is bivalent, carbon is tetravalent. There must therefore be twice as many O atoms as H atoms and four times as many C atoms and the sum must be the same on both sides.
| C8H16 + 12 O2 8 CO2 + 8 H2O |
| 8 * 12u + 16 * 1u = 112u + 24 * 16u = 384 u -> 8 * 12u + 16 * 16u = 352u + 8 * 1u + 8 * 16u = 144 |
Here the numbers of atoms left and right are balanced. The atomic mass of C is 12 times and that of O is 16 times that of H. These factors are each contained in the atomic mass unit 'u'. These are also the same with 486u
on each side. With an oxygen content of 23.16 percent, the necessary air mass is 1659u, with the proportion of fuel at 384u resulting in the so-called stoichiometric mixture ratio of 14.8:1.
The reaction equation is therefore based on the ideal that neither deviations from lambda 1 nor lack of time nor other circumstances prevent the individual molecules from reacting optimally with each other. Finally, for the
sake of completeness, the third reaction equation.
| 2 NO + 2 CO N2 + 2 CO2 |
How to set up a reaction equation
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