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Bonding: Ionic Vs. Molecular

Added Nov 12, 2015 •

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in this video we're going to look at compounds that are ionic versus compounds that are molecular also known as covalent will learn how you can tell them apart based on their formulas and then we'll look important differences between us so how can you tell whether something is ionic or molecular it depends on the elements that make them up ionic compounds are made of metals and nonmetals where is molecular also known as covalent compounds are made of only nonmetals let's do practice problems to work on this you will need a periodic table to do this here's one that I'm using I've left out a lot of the elements because they're not important what is important is a big thick staircase that divides the periodic table into two parts on this side of the staircase are the metals and on this side of the staircase are the nonmetals okay so here a couple examples the first one sulfur dioxide so where the elements It's Made it's made of sulfur and oxygen both of these are non-metals which means that sulfur dioxide SO2 is a molecular compound sodium chloride is made of sodium a metal and chlorine or chloride which is a nonmetal sodium chloride is an ionic compound right now H2O is made of hydrogen and oxygen know you might think that hydrogen is a metal because it's on this side of the periodic table science understandable if you do that but hydrogen is an exception even though it's on this side of the periodic table it's actually a nonmetal it's the exception so hydrogen and oxygen are actually both non-metals which means that H2O water is a molecular covalent compound okay copper II fluoride coppers here fluorine or fluoride is here metal nonmetal to the same as ionic okay let's look at a few Ricky your examples so far we've only looked a compounds that have two elements in it but there a lot of compounds out there that have more than two elements okay so propanol Snapple is made of carbon hydrogen and oxygen all three of these are nonmetals though so this is still a molecular covalent compound even though has a bunch of nonmetals in okay don't be confused by that here's another example lithium nitrate has lithium which is a metal are also has nitrogen and oxygen which are both nonmetals so it's still got the metal nonmetal thing going on so it's an ionic compound even though it has tuna house in the same thing is true of sodium sulfate it's got sodium a metal and two nonmetals sulfur in oxygen but metal nonmetal means it's ionic what's your nitrate and sodium sulfate are actually special kinds of ionic compounds because they have two different nonmetals in them they are what are called Atomic ionic compounds if you want to learn more about these I've got videos on them so now we can look at a chemical formula and we can sort them can we can decide whether something is ionic or whether its molecular covalent so what who cares will there are very important differences between ionic compounds and molecular compounds let's take a look at some of those right now so one really important difference is how the atoms in these compounds are all together in molecular or covalent compounds the atoms that make them up are held together because they're sharing electrons here's what I mean water H2O is a very common molecular compound it's made of one oxygen and two hydrogen in these lines between the atoms show that they're connected play means that are connected because they're sharing electrons here's our like to think about this it's like oxygen and hydrogen both have these little hands and hands are joined together like they're holding hands and they're holding hands because they both are trying to hold on to a pair of electrons which I've I'm here on red so got oxygen and hydrogen connected together because they're holding on and sharing these electrons here that's what makes the atom connect and stick together in a molecular covalent compound okay on the other hand ionic compounds the atoms aren't being so nice to each other okay not sharing the atoms stick together in an ionic compound because one atom steals another atoms electrons so electrons get stolen and then opposite charges attract want to show you what I mean sodium chloride or NaCl is a very common ionic compound it's made of sodium and chlorine I'm here they are just hanging out for these two guys to stick together here is what happens next thing that happens is chlorine pictures it's greedy hand over and grabs an electron from sodium so now chlorine has an extra Chad and sodium has lost one of its electrons this causes chlorine to now get a negative charge because it has a new electron and sodium because it's been had had one of its electrons stolen now it has a positive charge  so now we have a positive charge charged ion here in another negatively charged ion here what the opposite charged things like to do they like to come together they stick together their tracted to each other just like magnets so now we have a positively charged sing a negatively charged thing these Arrow show how they're going to come together and we end up with the two atoms stuck together because they're oppositely Arch and that's what hold ionic compounds together so covalent molecular compounds the atoms are stuck together because they're sharing electrons with each other ionic compounds the atoms are stuck together because one has stolen the others electrons it's given them opposite charges and then those opposite charges have there we go have a tracted just like magnets this is one way that ionic and molecular compounds differ here is more so another big difference is how these compounds would actually look if we could see the atoms that make them up so molecular or covalent compounds are made of molecules which is a fancy word for a bunch of atoms that are stuck together in a clump here is what I mean so sugar is very common type of covalent compound and it is made of molecules where have these atoms here stuck together in a clump two carbons 4 hydrogen and 2 oxygen of different sugar molecules that have all kind of Comedy are there informed Clump here okay big deal here is it these molecules are individual clumps of atoms that then come together to make stuff on the other hand ionic compounds they're not made of clumps of atoms like molecules are made of call lattice structures and here's what lattice structures are the example I'm going to give you a salt which is sodium chloride table salt and lattice structures of sodium chloride look like this what kind of different this is from the molecules that make up sugar you just have the sodium chloride atoms stuck together in the sort of very organized box like shape this is what a lot of structure is there aren't individual clumps of sodium chloride the way there are individual clumps of sugar instead all the atoms are stuck together in this very scalar shape important difference between covalent molecular stuff and Ionix is what happens when they dissolve in water why is just come apart into molecules where is the individual atoms come apart when an ionic compound is all tomorrow but we're getting a little ahead of ourselves here if you're interested in other differences between these check out videos that I have on the physical properties as well as what happens when you dissolve ionic and macular compounds

Uploaded by Laura Houston.

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Bonding: Ionic Vs. Molecular

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