Today we want to go over just some of the basics of chemical reactions. We don’t have time today to do this thoroughly or fully in depth, but just want to go over some of the basics of chemical reactions.
When we think about chemical reactions, one of the things we have to think about is time scale, how rapidly or slowly do chemical reactions take place.
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The transcript is provided for your convenience
In terms of time scale, obviously we’re measuring this from our vantage point, from our viewpoints, so on the human time scale, the way we experience time.
Chemical reactions can happen very rapidly, very quickly and also very slowly, from the lower end just fractions of a second for a chemical reaction to take place, all the way up to the upper end, years and years and years before a chemical reaction fully takes place and then everything in between. With chemical reactions, the time scale is from a fraction of a second all the way up to lots of years for them to take place and everything in between.
When we think about time scale we also think reaction rates, what affects reaction rates? In a chemical reaction, we need to think in terms of the frequency of the contact between the chemical components that are reacting. If it is very little contact, you have a slower rate. They don’t come into contact very often and also if there’s a great mixing of these things that reacts volatilely you can create rapid reaction. It’s the frequency of the contact between the interacting chemicals.
The temperate plays a role. Higher temperature or lower temperature can affect not only the reaction but then the time rate as well and then the properties of the chemical that is interacting. Is it a solid, a liquid or a gas? What shape is it in? Now all of these things play a part in the reaction rate, frequency, temperature, and properties. Then when we think about reaction rates, you can actually influence those rates. You can accelerate a reaction rate, this is called using a catalyst.
A catalyst is introduced in that chemical reaction which greatly speeds it up and that’s the catalyst only job, is to come into this interaction between these chemicals and speed up that reaction, that would ordinarily take place over a longer period of time, you rapidly increase it. You can also decrease reaction rates and this is called using inhibitors. If you introduced an inhibitor in a chemical reaction, it slows it down, it keeps them from reacting as quickly.
You can affect reaction rates, not only naturally and through ways that you are able to control temperature and what form it’s in, things like this. But you can also use other chemicals catalyst to accelerate to decelerate the reaction times of the chemical reaction. Now chemical reactions can when they occur release heat, release light, electrons, ions others usually some form of product from this interaction, this chemical reaction that’s taking place.
Sometimes chemical reactions sends the temperature in the opposite direction, but usually it’s things like heat and light, electrons being traded or spun off ions, your radicals going off, things like this. Finally heat and other factors can influence chemical reactions and help break bonds. You can think in terms of breaking carbon bonds. This is done obviously in the production of oil and related materials, you’ve got strong stable carbon bonds that need to be broken down and split up. Heat is usually the thing that is primarily used to break those bonds, divide those things up and then sort them out to their various functions and purposes.
If you ever do any sort of research and study it’s very fascinating to look at an oil or a chemical plant and how they bring in the raw materials using heat and other pressure and things like this to break up the raw materials brought in, into various other materials, sift it out and send to other places and put to other uses, it’s fascinating. Chemical reactions are just the basic overview again, timescale from fractions of a second, to years and years and years.
Reaction rates are affected by the frequency of contact, the temperature at the point of their mixing and their contact and then the properties, solid, liquid and gas or the shape of it, these sorts of things. Reaction rates can be accelerated with catalysts, decrease the inhibitors. Chemical reactions produce things often like heat, light, spinning off electrons, ions, things like this and heat and other factors influence chemical reactions and help to break chemical bonds.
Next Lesson: Nuclear and Chemical Reactions