So let's talk about first our main group elements. Remember, your main group elements are the elements found in Group 1A or group 12A or group 2, and then from 3A to 8 A or what we call groups 13 to 18. The elements here in the grayed out box, those are our transition metals. We'll talk about those later on, but for right now let's just focus on our main group elements.
Now recall that the atomic number which uses the variable Z of an atom equals the number of protons within its nucleus. For example, we'd say that beryllium has an atomic number 4, so it has four protons. For a neutral element, its number of electrons is equal to its number of protons. So beryllium here has an atomic number of four, which means it has four protons. And here, if we're dealing with a neutral element, it will have the same number of electrons, so it'll also have 4 electrons.
Now we said that all these elements of the periodic table are all trying to become just like our noble gases, our group 8A elements. They have the optimal number of electrons. Helium has two, Neon has 10, Argon has 18, and as we go down, these are all their atomic numbers, which gives us the number of electrons they have. Now elements try to gain or lose electrons to match each number of electrons for the normal gases. So noble gases, since they're perfect, their charge is 0, so they don't have a charge they don't need to gain or lose electrons.
Let's look at group 7A. All the elements in Group 7A flooring. Let's look at F Fluorine has nine electrons when it's neutral. If it wants to have 10 electrons, like neon, it would have to gain 1 electron. Chlorine has 17 electrons with neutral. To have 18, like argon again I'd have to gain 1 electron. So each element in this column would have to gain 1 electron to become like the noble gas next to it. By gaining that one electron they would get an A charge now of -1 because remember gaining electrons gives us a negative charge.
Oxygen, oxygen when neutral has eight electrons to have 10 electrons like neon. How many electrons would it need to gain? If you said two, you'd be right. So same thing with sulfur has 16 and have to gain 2 electrons to become just like argon. So this group 6A, its charge is normally -2. Nitrogen has seven, so to get to 10 you'd have to gain 3 electrons. So this the charge of this group is normally -3.
Now of course some of these groups that gets tricky because in Group five we see that we have nonmetals here, so they have a -3 charge, but then we have metalloids and then we run into metals. Metals don't want to have a negative charge, you want to have a positive charge. So these negative charges, when we're referring to them is predominantly with the non metal, the blue species. The elements are in the blue boxes.
Root 4 is a little bit tricky, so Group 4 is equal distance either way. What I mean by that is carbon could try to gain 4 electrons to become like neon or we could try to lose 4 electrons so that it has two like helium. So it's kind of been a special situation. So as a result of this we kind of just say non applicable to Group 4 based on their location the periodic table. Now though, we do have an exception that's around exception one, and this pertains to lead and tin. Lead and Tin are here SN and PB because of where they're located, how far down they are. They kind of have characteristics similar to transition metals. They can either be +2 or +4 for their charges. So just remember when it comes to tin and length, it can be +2 or +4. They're interesting situation when it comes to the periodic table and charges.
Now let's look at Boron and the other elements that are within this group. Boron is a metalloid metalloids. They have characteristics of both metals and non metals, so it's a bit tricky with them. So we won't be talking about boron, but we can talk about the elements below boron. Aluminum all the way down to New Hampshire. They're all metals, so they all want to lose electrons to become like a noble gas. Now, aluminum here, its atomic number is 13. So when it's neutral, it has 13 electrons. It has two choices. It can either try to gain 7 electrons to get, I mean not seven. You can try to gain 5 electrons to have 18 electrons just like argon, or it can do something easier than that. Instead of trying to gain 5 electrons, it could just try to lose 3 electrons so that it has 10 electrons like neon. And when it comes to chemistry, chemistry, we always go in the path that's easiest and fastest. OK, so it's easier for aluminum to lose 3 electrons than to loop to gain 5 electrons because it's more spaces that you have to jump to become a noble gas. This way easier just to let go of your 3 electrons. So because of this, this group tends to be +3 for its charge.
Beryllium. Let's look at beryllium. Beryllium has an atomic number 4, so it has two choices. It can either try 2 what gain 6 electrons 123456 to become like neon, or do something easier, just lose 2 electrons so that it has two electrons just like helium. So the easier and shorter path is to lose electrons. So it's this. This group tends to be +2. Then finally, again, we're talking about the metals. They're the ones who want to lose electrons to become positive. Hydrogen is not a metal, so we don't talk about hydrogen in this regard. But we'd say that lithium could try to gain 7 electrons to get to 10 like helium, which is a long distance to cover. Or the easier thing would be just to lose 1 electron and become like helium. So this group tends to be plus one.
So these are the charges that you need to commit to memory when it comes to these different groups, group 1A plus one, group 2A plus two then plus three. Fourth group is not applicable. Group 5A is -3, then -2, then -1. Noble gases are perfect, so they don't want to gain a charge. Now, exception 2, we're going to say this pertains to our heavy metals of bismuth, polonium, and those that have atomic numbers from 1:14 to 1:18. Because of their position on the periodic table, they're a little bit weird and they have multiple types of charges, so we tend not to talk about them. But when it comes to main group elements, just keep in mind the major charges that we've listed, plus 1 + 2 + 3 -, 3, -, 2, and -1. And then of course your exception one. This is what you need to take away from the main group elements and their various charges.
