[Music] hello everyone welcome back to teach me to science and today we're going to be talking about collision theory first we're going to define what collision theory is then we're going to talk about orientation and temperature and how they affect collision theory and then we're going to dive into some reaction steps collision theory in its most basic sense is the idea that atoms or molecules have to collide in order to react however it's a little bit more complicated than that in order for atoms to react successfully they also must collide in the correct orientation and with enough energy the correct orientation means that the atoms must be physically lined up correctly in order to react for example I've got some molecules drawn below which show that the reaction only occurs when the black atom on one molecule interacts with the white atom on the other if they happen to collide with both of the white molecules hitting each other then no reaction will occur it's also important to note that molecules do not choose how they collide chemists often talk about molecules and atoms as if they have choice in the matter but they really don't the molecule is simply floating around in solution and may or may not collide with another molecule which will create a reaction now this is where temperature and concentration come in there are some things we can do to increase the likelihood that the molecules will successfully interact one of them is to increase the temperature an increase in temperature causes the molecules to move around more and faster and increases the likelihood that they'll collide likewise increasing concentration will also increase the likelihood that they will collide because there will be more molecules bouncing around within the solution for this reason if you want a reaction to occur more quickly then you will increase the temperature and increase the concentration the final concept I want to introduce is where reaction steps come from so here I've drawn three molecules colliding in the exact right way to create a reaction this is possible but not very likely now imagine that I have a reaction that we're where's four or five or even six different molecules to collide the probability that six molecules have enough energy and the correct orientation to properly react is not very high and this is where reaction steps come from reactions occur in two steps because they are more energetically favorable reaction steps allow for multiple molecules to collide correctly with enough energy so that they can create an intermediate product which can then go on to react with the other reactants in the reaction now that might sound a little bit confusing but picture it this way sometimes baking recipes call for you to mix certain ingredients together while not mixing them with other ingredients commonly I can think of you mix wet ingredients and keep them separate from dry ingredients this is because wet ingredients mix together easier this is kind of like a reaction step you mix the easiest things together first and then you mix the wet and a dry because they're more difficult to combine this is exactly what reaction steps do they mix together fewer things to make it easier and more likely for the reaction to occur all right that's all I have for this video on collision theory I hope you found this video helpful and please like this video and subscribe to my channel I really really appreciate it have a nice day bye [Music] you