Covalent vs. Ionic bonds

okay let's talk about the basic differences between ionic and covalent bonds two different ways in which atoms can connect to one another well let's first look at the basic parts to an atom here is a square from the periodic table B E is the element beryllium and elements are made from atoms and atoms have three basic parts first of all there are the protons these are the parts that have a positive charge from the periodic table square I know that from looking at the atomic number beryllium has one two three four protons another part of an atom is what is called what are called electrons these are parts that have a negative charge usually the amount of protons is the same as the amount of electron so I now know that beryllium has one two three four electrons and then the third part to an atom are called the neutrons now be careful the number 9 and the square that's not the number of neutrons the 9 is when you add up the combined amount of protons and neutrons in in beryllium zigzagoon - Trent's will equal 9 so we just got done saying there's four protons plus how many neutrons will give us nine simple math there is going to be a total of five neutrons so how are these parts arranged well atoms have a nucleus and in the nucleus are the protons and the neutrons surrounding the nucleus are these levels of electrons now the levels of electrons you might know can only hold a certain amount the first level the inside level can carry two electrons to makes it full or stable the second level can carry eight electrons eight electrons will make the second level full or stable and even though beryllium doesn't have a third level many atoms do and if an atom has a third level eight electrons will make it full or stable so let me put two electrons in the first level of beryllium and the electrons kind of orbit the nucleus and so now that first level is filled it's what we call stable well the other two electrons have to go in the second level and here's the problem with beryllium it's unstable it's unstable because the second level is not filled the second level can carry eight electrons but there's only two that makes it unstable so why do atoms bond with one another well they bond with one another to become stable and what that means is that they are trying to obtain more electrons so they can fill their levels now there are two basic types of bonds and that's why you're watching this videos to learn the difference between the covalent bonds and the ionic bonds let's go over covalent bonds first okay so the basic definition of a covalent bond it's a bond between atoms where they share electrons and so the goal of the of atoms forming covalent bonds is to become stable to fill their levels of electrons and the classic example of this is oxygen Li the oxygen that we breathe o - the oxygen that plants make by doing photosynthesis is actually two atoms of oxygen stuck together so let's look at oxygen from the periodic table it's got eight protons it's got eight neutrons so let me draw oxygen number one I'll get two oxygens electrons in a moment so in the nucleus of oxygen number one are going to be eight protons and eight neutrons well I'm also going to draw the electron levels around the nucleus and now I can tell you that oxygen has eight total electrons so when I draw the electrons I'll put two electrons in level number one because that's all level number one can carry and then I'll put the leftover six electrons in level number two in the end notice how the first level the inside level is stable because it can only hold two and it has two but the second level is unstable it can carry eight electrons but it only has six that's a problem it's unstable well the oxygen that we breathe is actually made from two atoms so we have to draw a second oxygen atom like the first it has eight protons it has eight neutrons in the nucleus it will have a couple levels for the electrons and it's got eight total electrons so just like before I'll put two electrons in level number one I'll put the remaining six electrons in level number two so the first level is stable it's filled the third level is unstable it's not filled it doesn't have eight electrons it only has six so what's going to happen when these two atoms are both unstable well in this case they're going to form a covalent bond they're going to overlap their electron levels and share their electrons so when you count up the electrons of oxygen number one one to level number one is stable how about level number two level number two has one two three a shared fourth a shared fifth six seven eight level number two was once unstable but it is now stable because of the sharing of electrons let's look at oxygen number two oxygen number two has one two electrons in the first level first level stable look at the outside level one two three four a shared fifth six seven a shared eighth because they're sharing electrons oxygen number twos outside level is now stable so if I set those electrons in motion you know those shared electrons are zigzagging back and forth kind of like in a figure eight right here and because of this sharing of electrons both oxygens oxygen number one oxygen number two they have filled outside levels that's a covalent bond let's look at an ionic bond next so the definition of an ionic bond it's a bond where one atom gains an electron and another looses remember atoms make bonds in order to become stable they're trying to fill their levels of electrons a classic example is sodium chloride na is sodium CL is chlorine you put the two together you have what's also called salt well here's the square for sodium from the periodic table the eleven is the amount of protons that's the atomic number I know sodium has 11 protons so there they are if you remember from earlier the protons and the electrons are usually found in the same amount so I now know sodium also has 11 electrons the 23 on the bottom is the mass the combined protons plus neutrons for sodium adds up to 23 so we just said 11 protons plus what mystery number equals 23 simple math sodium has 12 neutrons all right let's put this together now so let's put this atom of sodium together the protons and neutrons are clumped in the nucleus I'm going to add one two three levels for the electrons you'll see why I added three in a moment level number one can only carry two electrons hey at least it's stable it's filled level number two can hold eight electrons so I'll put eight of them in level number two level number three can carry eight but there's only one left over so when we look at the levels level number one is stable level number two is stable level three is unstable level three can carry eight electrons but there's only one that makes it unstable all right I want to put that note in the upper left-hand corner to remind me that sodium has 11 protons 11 electrons it also has 12 neutrons but because neutrons have no charge we don't need to focus on them I want to shift focus away from sodium to now I want to shift our focus to chlorine from the periodic table the 17 is the atomic number or the amount of protons if you remember the proton number is pretty much always going to be the same number of electrons so I now know chlorine has 17 electrons the mass is 35 that's 17 protons plus what number equals 35 that means chlorine has 18 neutrons so now I want to draw the chlorine atom it has 17 protons it also has 18 in the nucleus so now when I draw the electron levels one two three levels for the electrons I got to draw 17 electrons I can only put two electrons in level number one it's filled it's stable that means there's 15 electrons I have to account for I cannot put all 15 or level number two but I can put eight and level number two that will leave me a total of seven to account for I can put all seven in level number three I hope you see the problem though level number three is not filled it's not stable so look at level number one for chlorine it's stable because it's filled with two electrons look at level number two it's stable because it's filled with eight electrons the problem lies with level number three it's unstable it's not filled there's only seven electrons in level three eight will make it stable so just like last time with sodium I want to put a reminder in the upper right-hand corner for chlorine chlorine has 17 protons 17 electrons I want to see that to remind me as we go through the next part look at my definition an ionic bond is where one atom gains an electron but another loses watch what chlorine does is three to one chlorine is stealing an electron from sodium that's going to completely change the amount of electrons that each has sodium used to have 11 electrons but it just lost one it only has 10 chlorine used to have 17 electrons but it just stole one it just gained one it now has 18 well let's look at the levels of electrons to see if they're stable sodium on the left two in the first it's stable eight in the second its stable it doesn't even have a third level anymore that's okay look at chlorine on the right two electrons in the first level it's stable eight electrons in level two it's stable chlorine used to have an unstable level three but it just took an electron from sodium it now has the desired amount of eight in level three it too is Abell but how do these things actually stick together watch this sodium on the left is actually like a positively charged magnet now it has 11 protons protons have a positive charge and only 10 electrons electrons have a negative charge so because it has more protons it's positively charged chlorine it's just the opposite chlorine now has more negatively charged electrons that gives it a negative charge what happens when you put a positive and a negative magnet together they stick they bond with one another the positive charge of sodium is attracted to the negative charge of chlorine like two oppositely charged magnets magnetism draws them together and that's what holds them together in an ionic bond sodium is a positive magnet chlorine is a negative magnet they bind together ionic Li so there you have it the basic differences and similarities between covalent bonds and ionic bonds go ahead and pause the video if you want to compare and contrast the two I hope you found the video really helpful you know leave your thoughts below in the comment box I look forward to reading them take care best wishes to you

Channel: Beverly Biology

Views: 758,520

Rating: 4.863986 out of 5

Keywords: Ionic Bonding (Chemical Bond), Covalent Bond (Chemical Bond), Chemical Bond (Literature Subject), Chemistry (Field Of Study), Periodic Table (Invention), atom, Electron (Subatomic Particle), Table Salt (Ingredient)

Id: VSc491HLzDo

Length: 12min 22sec (742 seconds)

Published: Thu May 28 2015