in today's video we're going to take a look at the reactivity series of metals and see how metals react with both acids and water then to finish we'll take a quick look at how we use the reactivity series to figure out what will happen in displacement reactions if you remember the electron arrangement of metals what they all have in common is that they have electrons in the outermost shell that they want to get rid of and so when they react with other substances they get rid of these outer shell electrons and form positive ions so when we talk about the reactivity of a metal all we mean is how easily it forms these positive ions the metals that form ions most easily are the most reactive and by comparing all of the metals we can arrange them in order of their reactivity like this which we call the reactivity series now even though carbon and hydrogen aren't metals we often still include them in reactivity series as references to compare the metals against the most reactive metals are the group 1 metals with the group 2 metals being a bit less reactive and the transition metals generally the least reactive to figure out this list in the first place though we need to react each of the metals with either acid or water and compare their relative reactivity by seeing how fast or violent the reactions are if we react a metal with an acid it will form a salt and hydrogen gas for example if we reacted potassium with hydrochloric acid it would form potassium chloride and hydrogen and because potassium is so reactive it would react explosively possibly catching fire and whizzing around as it produces loads of hydrogen the reactions would then get gradually less violent as we go down the series and by the time we get to magnesium it would just produce lots of bubbles as the solid metal disappears in the acid we'd then see fewer bubbles with zinc and iron and copper usually won't react at all rather than just watching the reactions to see how violent they are we can also measure the temperature change of the reactions because the most reactive metals will produce the most heat if we're going to compare the metals though we need to make sure it's a fair test by ensuring that each of the metal samples that we use has the same mass and same surface area and that we use the same type and concentration of acid each time now if we instead react metals with water rather than acids they form metal hydroxides and hydrogen for example lithium plus water would go to form lithium hydroxide and hydrogen however only the most reactive metals are reactive enough to do this zinc iron and copper won't react at all while magnesium will only react very slightly now the last thing we need to cover is displacement reactions the idea here is that more reactive metals can displace less reactive ones so if we put some magnesium into a solution of iron sulfate then the magnesium would displace the iron to form magnesium sulfate plus iron because the magnesium is more reactive than the iron whereas if we added copper to a solution of iron sulfate then nothing would happen because copper is less reactive than iron so you can't displace it anyway that's all for this video so if you enjoyed it then please do give us a like and subscribe and we'll see you next time you