in this video we're going to talk about how to determine if a compound is soluble or insoluble using the solubility rules a soluble compound is one that dissolves in water one that is insoluble does not dissolve in water so in an ionic compound if you see group one metal ions like sodium potassium lithium rubidium and things in that column they are always soluble that's the general rule ammonium is also always soluble and if you see any of these two polyatomic ions nitrate acetate it's always soluble now you might find some rare exceptions but for the most part if you have a test and you see those two generally speaking is going to be soluble now the halides like chloride bromide iodide these are generally soluble fluorides a little bit different the exceptions to those are silver lead 2 plus and mercury 2 2 plus so if you were to see pbr2 that would be insoluble because with pb bromide pb is an exception for bromide now sulfates are generally soluble the exception is certain group two metals like calcium barium and stratium and also lead two plus hydroxides are generally insoluble except with group one metals like sodium lithium and potassium ammonium and also the heavy group 2 alkaline earth metals like calcium strontium barium magnesium hydroxide is somewhat soluble in water so that's like the borderline there but below magnesium you have calcium strontium and barium hydroxide is soluble with those metal ions now focusing on the last row sulfide carbonate phosphate and chromate these ions are generally insoluble but they will be soluble with these guys the group 1 metal cations like sodium potassium and lithium and of course with ammonium so those are the general solubility rules that you need to be familiar with if you know this this is good enough to determine if a compound is soluble or insoluble now let's put this information to work let's put it into practice let's work on some example problems let's start with this one sodium phosphate is it soluble or insoluble based on the solubility rules anytime you see a group one metal ion like sodium potassium and lithium it's going to be soluble and so we're going to represent this using the phase aq aqueous which means that it dissolves in water now what about potassium chloride well potassium is a group 1 metal so that also will dissolve in water now silver chloride chlorides are generally soluble with the exceptions of silver light and mercury so because that is an exception to being generally soluble this is going to be insoluble and we're going to write s because if you were to mix sodium chloride in water it's going to remain a solid it's not going to dissolve into the aqueous phase now what about lead 2 nitrate nitrates are always soluble so we're going to put that in the aqueous phase next potassium sulfate potassium is a group 1 metal cation and so that is going to dissolve in water that's soluble so we're going to write aqueous lead 2-sulfate sulfates are generally soluble but lead is an exception so this is going to be insoluble in water next we have potassium hydroxide potassium being a group 1 metal that's always going to be soluble so we're going to write aqueous for that now it might be a good idea to pause the video take out a sheet of paper and try the remaining examples yourself determine if these compounds are soluble and insoluble using the solubility rules that we discussed earlier in this video so feel free to take a minute to try these problems and then play the video to see if you got the answer so let's start with barium hydroxide is barium hydroxide soluble or insoluble hydroxide are generally insoluble barium is an exception which makes it soluble now magnesium hydroxide that's different magnesium and barium they're in the same column they're both grouped to alkaline earth metals but magnesium hydroxide is somewhat insoluble so we're going to put solid for that its solubility is very very low in water in fact is used as magnesium hydroxide is used as a laxative in the milk of magnesia product lithium carbonate lithium is an alkali metal it's a group 1 alkali metal so it's going to be aqueous it's in the same category as sodium and potassium magnesium phosphate phosphates are generally insoluble with the exception of group 1 metal cations so this is going to be a solid ammonium this is always soluble so we're going to write aq for that sulfides are generally insoluble so we're going to put s silver nitrate nitrates are soluble that's one of the first rules so that's going to be aq and then for the last one iodide is a halide which is generally soluble but lead is an exception so we're going to put solid for that so that's basically it for this video now you know how to determine if a compound is soluble or insoluble using the solubility table thanks for watching