Periodic properties part 7

Added: 2026-05-15

[00:00:00]now continuing with the periodic properties today i'll teach you that is how to name the compounds whose atomic number is more than 100 see below atomic number 100 we are having the name of the compounds like sodium means nitrium we give the symbol in a for potassium calcium we give the symbol k so actually these names are given by the scientists either upon their name or the name of the place from where it belongs to or something like that whatever it is it is going by the scientist now the confusion arises ok or the confusion arised rather rather i should say when several scientists came into being for the discovery of one particular element previously what it was happening one particular scientist was discovering one element so hence entire credit goes to that regular scientist and accordingly he named the particular element whatever he feels like clear but when several scientists came for the discovery of a particular element several scientists means suppose a scientist is from russia another is from denmark another is from scotland another is from india or another is from let us say america three or four scientists are included in that particular research for the discovery of particular element so the indian wanted to name it in their manner american wanted to name it in german and russian wanted to name it in their manner all right so the confusion arrived there only so iupac decided to avoid this particular confusion the elements whose atomic number is more than 100 it will be named according to the iupac system according to the rules which will be assigned by the iupac system they also decided that below 100 we will not name those particular elements because we will not dis disrespect the scientist but it hence they decided that above 100 the elements which are there it will be named according to the iupac rules according to the iupac system got it now that why above 100 we're taking why not below 100.

[00:02:06]all right the reason is this all right fine now how will you name it it's very simple it's not so difficult you have to remember little bit few things now for example 0 it is nil for one it is on then two it is by three it is try four it is quad five it is pent six it is hex seven it is set eight opt nine is n don't say ten ten means one zero only got it in this way now why did i write this particular one why did you write it the reason is that suppose an element is there whose atomic number is 105 and element is there is atomic number is 105 how how will i write this particular element what is what should be the symbol of this particular element all right what what should be the iup is the name of this particular element all right yeah so it is being written in this way see here so for one what i have written and u and n the first letter of that particular one is taken from as a symbol now wait 0 is what nil for 5 is what it is paint and the last we will be adding yum to all the names to all the names we'll be adding yum and what i said the first letter is taking 1 it is u for 0 n and for 5 this p so hence the symbol you got it u n p the symbol you got it u n p in this way the symbol you got it all right this was the symbol this symbolically it was being taken so the rule is that what you have to do is that first you have to remember this it's quite easy not not difficult thing then after that you'll be writing in this way and at the last for all the names you'll be adding yum to it yum for the last so hence what is the name you got it now you're not writing this one plus mean plus just i showed you what you will write it that is here 2n is there altogether 3 but you can take 2 maximum so anil pent this is the iupac name of the element whose atomic number is 105. suppose the element if it is not discovered let us see the element is not discovered but the image is the word the symbol is discovered alright the symbol is u n p the name is anil pentium suppose you say an element is there whose atomic number is 132. let's see total 118 is there isn't it just i'm saying hypothetical case i'm giving you let us say 132 element is discovered let us see but before that you can write the name according to the iep signature system you can write the name the name is written in the periodic table does not mean that the element is discovered you might be thinking that you if you see the periodic table you'll find that all 118 elements this name is there but it does not mean all the 118 elements is discovered what it or we are knowing the properties of all the elements no not not at all i've said it i have said it in the previous area so here what should be the name it is for three it is try got it let me write it directly it is try for two it is by and for at the last you'll be adding yum so what is untry by m it will be what should be the symbol the symbol will be u all right first one then from three it is t all right and from 2 it is y so u d b you can say this is a symbol this is symbol we can say that in this way the symbol is being given the name is being given for the element whose atomic number is more than 100 so you have to remember this first you need to remember most of things you know it then after that you need to write in this way all right you need to write in this particular way see i've written it here the two examples are given so now you can write the name of any atomic number any atomic number what you can say you can write the name and you can also write the symbol at the same time the first letter is capital the second and third it is small it should be the same rule but you are having it previously all right fine so in this way you came to know that how to write the iupac name of element was atomic number is more than hundred done now we will come to know that a particular element but in the periodic table we have got 2 8 8 18 18 32 elements are there all right now if it is asked in the exams that you what you can say justify that the third period consists of eight elements or the fifth period consists of 18 elements you justify it how you justify how will you justify i am justifying it now see it for all the periods i am justifying it now got my question the question is there in a book that justify that the fifth period consists of 18 elements how is this to find see i'll see very easy your main column i am doing for all the periods understood you just do for one period whichever it comes period first of all then number of energy [Music] level all right number of energy level being filled how many energy levels first second third fourth in this way and we will be writing it out then after that sub shells being filled i have to write it small i will not have space then after substance being filled you will be writing it out that is nothing but number of electrons of that elements all right or number of uh electron of that element in a particular period a number of elements of that element in a particular period let me write it number of electrons e minus or elements both are written in a period in a given period we can say that so fine now see period it is ah n is equal to 1 then n is equal to 2 n is equal to 3 n is equal to 4 and is equal to 5 and is equal to 6 n is equal to psi in this way clear that is seven periods we got it now number of energy levels is also the same thing suppose if you take it here one two three four five six then here it will be number of energy level means n is equal to one same thing you can write it down same thing this all right so here you do one thing vector is that you write it here one two three four five six and here you write it as this because number of energy level means enough so it will be better for you to understand otherwise both the it is got it no fine now sub shells being filled now here you have to understand the first shell consists of how many subshell one is second shell consists of how many subshell 2s and 2p yes or no third shell consists of 3s 3p and 3d we can select clear so the third cell that is n is equal to 3 sorry 3s and 3p we can say and the fourth shell that is 4s 3d and 4t in this way 4s 3d 4p it will be 5s 4d 5p the fifth one i have written it then sixth it will be 6s 4f 5d 6p i don't have the space 6s 4f 5b and 6p similarly for the 7th you write it down 7s 5f 6d 7p correct now you see it here now s subshell maximum how many electrons two sorry two now here is subshell two and p subshell six so two plus six is how much eight the second period consists of all numbers eight now third cell again s and p s is two maximum two p six so it is eight now fourth you see s is two then uh d is ten and p is six it is what 18 same thing here also same thing two plus ten plus six it is eighteen here you see it is 2 plus 14 plus 10 plus 6 here s f d p 2 maximum electron something 2 electrons then 14 electrons then 10 electrons and 6 electrons which you get it as 32 got it put it plus 2 it is let me put a line here so that it will be differentiated clearly so for 14 plus 2 16 plus 10 26 the 6 32 and this way for the seventh also you'll be doing in this way you'll be getting thirty two elements got it seventh maximum thirty two we can say that clear so in this way you can justify that suppose it's asks that fifth period yeah fifth period you'll write only this one n equal to five this 5 s 4 d and 5 p substance it contains and as a result the number of maximum number of electrons can be 18 so hence the fifth period can contains maximum 18 elements or 18 electrons whatever you can say that clear so in this way we can justify this is very important questions i've discussed with you fine after that another very important questions it will be asked to you that find out suppose an element is given atomic number is given all right atomic mass also may be given to you atomic number may or may not be given minutes you have to learn it the atomic number up to 40 you need to learn it the atomic number of 240 all right i'll be saying i'll be sending you a shortcut method how to remember it up to atomic number 40 so to say okay so whatever it is suppose an atomic number is given element is given atomic number is given and atomic mass is given clear so you will be asked with your mind that in which period it belongs to in which group it belongs to in which block it belongs to what is the valency whether it is a metal non-metal and etcetera etcetera question will be asked but okay main is your period block and group so how to find it out that i am going to say you know all right understood my question an element will be given atomic number atomic mass will be given you have to find it out the period block and group of that particular element you need to find it out all right clear fine for example let me take here that is let us say here sodium atomic number 11 all right or and let me not write sodium let me write here x atomy 11 i don't know what is that elemental axis because if i give sodium limit is i'll mark it up okay and you can say the answer but i have not given you the element i have written it as x let's say now first what you need to do is that atomic number is given means write the electronic configuration 1 is 2 2 is 2 2 p 6 3 s 1 so the highest print principle quantum number gives the number of shells or number of period so the period in which it belongs to is third period see the highest principal quantum number is three so these elements belongs to third period the highest principle quantum number determines the period mind it size principle quantum number is three now we will find the group then i will go to the block so which group i told you the last electrons which enters into a particular sub shell that determines the group so last electrons enters into s subshell so it belongs to that is sorry i'm group i'm saying block sorry that is block first block then group so last electrons enters into s sub shell so it belongs to s block we can say that it belongs to s block last electron last electron in which in whichever subshell is entered suppose it enters into p substitute p block if it enters into d subshell d block if it ends enters into f sub so f block in this way first we find the block then after that the group so group is if an element belongs to s block remember it it has only two groups either it can be group one or it can be group two so how do we find it out from the valence electrons what is a valence electron here one because these are valence elements this is outer motion isn't it the valence electron is one so it is group one if an element belongs to s block remember it for every block the formula is different the finding is different if an animal belong if an element belongs to s block then it can have only two groups you know it group one group two how do you find it out the valence electron determine the group the valence electron is one so one suppose you have in here two then two can you have three here no because maximum consider your substrate is two only so hence it it has only two groups group one group two in this way you need to write the electronic configuration first then find the period then the block and then the group so in this way you understood for the s block now we will come to that let us say we will come to the p block let us take an element ah the let us write the atomic number and let us find it out okay now let me take another element here y got it whose atomic number is what should i take it is here that is nothing but it is 15 minus atomic number 15 and giving you a smaller one got it so 15 so 1 is 2 2 is 2 2 p 6 3 s 2 3 p 3 let us count it and see 6 for 10 to 12 and 3 15 correct so we got it 3 p 3 so what is the period in which it belongs to that is third p period because his highest principal quantum number is three you can see here three so period is third period then after that we'll find out the block block is last electrons enters into p block p subshell you can see so it is p block block is p see the last electrons enters into the p substance it is p block then after that group now here the form lines listen carefully 10 plus for the p block if an element belongs to p block then to find the group the formula is 10 plus number of electrons in valence shell listen carefully here see carefully number of electrons in balance shell 10 plus so what is the number of electrons in valencia it is this this is your valence shell this is your sub shell this is a sub shell minded s and p are the subshell so this is your balance shell in the previous case only one was there so i said that is that three s one in the previous case it was there so i said this is the last shell yes only one suction was there but here two sub shells are there so two substance will determine one shell yeah because this is also three this is also three so it belongs to third shell and it has got two suctions mind it i have written it as shell here not subshell all right so listen carefully all of you sense it will be ten plus how much five so it is group fifteen so two plus three see number of electrons in valencia how many it is five electrons is there in the valence shell so hence it is belong hence it belongs to group 15 within so that clear period third block p and group 15 we can say clear so this way we can determine the group of the p block 10 plus number of electrons in the valence shell see this i am saying repeatedly understand it this is your sub shell this is your sub shell but together it is a shell its outermost shell the valence shell clear now next if an element belongs to d block how do you find it out d block for example let us write it down here z 25 let us write it down here so it will be 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 4 is 2 3 5 counted in c 6 4 10 to 12 6 18 to 20 25 fine so we got so what is the period here which period it belongs to highest principle quantum number c4 this is your outermost shell mind it because only one sub-shell is there this outer motion see highest principle quantum number so period fourth it is not necessary that the one which is written in the last it should be the last shell i told you this one earlier also i have explained you alright so highest principal quantum number is force it is the fourth period this is outermost shell also mind it now next is in which block last electrons enters into d suctions it is d block which group for the group the formula is 2 plus n minus 1 d electrons where n is equal to highest principle quantum number quantum number highest principle quantum number 2 plus n minus 1 d electrons fine so 2 plus n is here what is the highest principal number 4 4 minus 1 it is 3 so it is 3 d electrons in 3d how many electrons is there 5 so hence 2 plus 5 so it is 7 understood don't write 3d 5 you have to only want the number of electrons here what i have written n minus 1 d electron 2 plus and say here i want the number you know it right here 3d5 can i add 35 plus 2 got it have some common sense so in this way i want the number of electrons here so number of electrons in 3d is how many five electrons is there because what i have written n minus one n is highest principle but highest is four four minus one is three d in three d how many electrons is there five electrons suppose your highest would have been five five minus one is four four d in four d you find out how many electrons is this how many electrons have written c electrons n minus one d electrons what a two plus so hence it is it belongs to which group it is group 7 all right now if an element belongs to f block you write electronic configuration if you find it and if the last electrons enters in the f suction if an element belongs to f block i have told you earlier it has got only one group that is group three because for that reason only f block elements are called inner transition elements because it lies within the transition elements you see your periodic table you will find it out that block elements belongs to group three so if an element belongs to f block no need to find the group the group is three for all the elements the group is three you can see the period properly you'll find it out you'll get the answer alright so period is determined by the highest principle quantum number block is determined by the electrons which is entering into which particular subshell and the group is determined accordingly which i said and the valence electrons also i have told you how it is determined if an element below if an element has got one two or three valence electrons it is a metal if it is four it is a mechloid if it has got five six seven valence electrons it is a non-metal and eight you know is an inert gas you know everything so in this way we can determine the group period block and all the steps thank you