 okay right now next one more compound we have first we write down aluminium chloride kscl3 two compounds we have to discuss the alum and aluminium chloride aluminium chloride write down it is obtained from the reaction of IHCl AlCl3 dry HCl or chlorine gas chlorine gas reaction of dry HCl or chlorine gas aluminium in the absence of air rather there is no moisture l plus aluminium l plus 6 HCl it forms AlCl3 plus H2 gas similarly aluminium with chlorine gas forms AlCl3 AlCl3 right on next slide hydrated aluminium chloride fitted aluminium aluminium chloride is obtained by is obtained by dissolving aluminium metal is obtained by dissolving aluminium metal or aluminium hydroxide or aluminium hydroxide in dilute HCl so Al this HCl here it is dry with two HCl it forms hydrated aluminium chloride AlCl3 and H2O molecule present around this okay so that is hydrated form of this even if you take aluminium or AlOH whole thighs with HCl diluted HCl it again gives you the same product that is hydrated AlCl3 hydrated AlCl3 generally will write AlCl3.6 H2O hydrated aluminium dilute means what what does it present actually this is again again a coordination compound okay it's the actual structure I think it will be like this H2O begins on the ligand it will be 6 and Cn3 will be right this molecule so what this you don't write now we will discuss this in coordination number okay depending upon this coordination number only we'll have the number of water molecule present like coordination number of Al H2O whole 6 is 6 there because aluminium attached with 6 water molecules coordination number is 6 so depends upon the depending upon the coordination number we'll have the number of water molecule present what is coordination number and all in detail we'll discuss that okay next you write down it is used as a catalyst in friddle crop reaction friddle crop reaction what is friddle crop reaction alkylation and acylation what is the reaction alkyl benzene benzene plus rx gives benzene and r attachment okay in terms of aridus and another one is acyl group see alkylation is what it is the reaction of alkyl light is benzene acylation is reaction of acyl group with benzene rcox with benzene this is acyl group acylation is friddle crop acylation is this okay next write down write down it reacts with lh4 OH and forms a white precipitate of reacts with lh4 OH and forms a white precipitate of white precipitate of al OH whole price al OH whole price it reacts with lh4 OH and forms white precipitate of al OH whole price so it reacts with lh4 OH and forms a white precipitate of al OH whole price okay so what what is the reaction what it is al cl3 with lh4 OH gives al OH whole price plus lh4 cl okay white precipitate of aluminium hydroxide okay next reaction you write down next reaction you write down next compound it is lm lm the formula is k2s4 dot l2s4 whole price hydrated form it is dot 24 h2 lm is a general form general name of this this is potassium and aluminium salt so would you call this an acid like a formation it's not an acid it's a hydrated compound of the salt of potassium okay when you dissolve this in water it converts it to k plus al3 plus s4 2 miles in water molecule okay in this write down structure is like uh see it is a double salt type like any steel structure can see that in right so it's a double salt in this we have k plus i present al 3 plus i present and some it's the crystallized structure it is not a constant compound it's a double salt so is the k part and the real part are bonded together and this is a additional compound like this aluminium is associated with SO4 also so you'll have that structure you can draw k SO4 k2 SO4 like this k SO4 2 minus so we can draw this as it's a salt right it will be 2k plus SO4 2 minus because this k plus and SO4 minus all these ions are present see actually 2 and 3 plus plus 3 SO4 2 minus like this again in the solution we have all these ion presence which how do you get this you have water water may you can do yeah the entire thing is this is not one structure it's a salt it's hydrated form of this okay so for aluminium again if you talk about this and this we can take in this in this we can take so here we have the coordination number of this and the coordination number of this total the water molecule is coming out to be 24 h 2 okay that's why it is 24 h 2 it is the general form actually of alum we can also call it as it is a potassium and aluminium salt of this potassium and aluminium sulphate salt of is nothing but the alum right so in this right down it is a double salt it is a double salt in which we have two different metals here potassium aluminium like what this compound the name is potash alum this is called a potash alum because potassium is there potash alum we can also take here chromium instead of aluminium we can also write chromium that is chrome alum so alum is a general name okay potash alum and chrome alum next right now it is prepared from box size 4 it is prepared from box size 4 what is the formula of box size right on box size is heated with or boiled with H2SO4 to form aluminium sulphate Al2SO4 both things with concentrate concentrate H2SO4 H2SO4 forms aluminium sulphate in which K2SO4 is added and the resulting solution is concentrated in so the reaction is Al2O3 with H2SO4 it forms Al2SO4 whole price and H2SO4 now in this we add K2SO4 and the entire thing when resulted in good we get Al2SO4.Al2SO4 whole price 24 H2SO4 this is nothing but potash alum or simply we call it as Al2SO4 okay property right down in a white press line compound white press line compound white press line compound it is solubilion water it is solubilion water and its and its aqua solution and its its aqua solution is acidic in nature but because this part Al2SO4 whole price is goes in the hydrolysis into this okay solubilion water and its aqua solution is acidic in nature so acidic why because this Al2SO4 whole price reacts with water forms AlOH whole price and H2SO4 that's why the solution becomes acidic okay right on on heating on heating on heating 200 degree Celsius it eliminates water molecule eliminates water molecule so it forms K2SO4 not Al2SO4 whole price and 24 H2SO4 on red heat further if you heat this compound it converts into K2SO4 on red heat forms K2SO4 and Al2SO4 dissociates into Al2O3 and H2SO4 because simply write this as Al2SO4 also right next to write down carbon family what are the elements we have our atomic number is 4 1s2 oh 1s2 2s2 2p so general outermost electronic configuration is ns2 and between going of atomic here ns2 and between there are four electrons in the outermost shell so it can show plus 2 and plus 4 oxidation state the possible oxidation state is this again the general trend is as you go down the group the atomic radius atomic radius increases metallic character metallic character also increases down the group as ionization energy decreases write down the next thing ionization enthalpy ionization right down the first ionization enthalpy the first ionization enthalpy of the elements of group 40 ionization enthalpy of the elements of group 14 is higher than the elements of group 13 what about atomic radius 13 and 14 13 is why effective nuclear charge effective nuclear charge okay so ionization enthalpy of group 40 elements is more than to that of group 30 because of lesser size more ionic more effective nuclear charge down the group if you go the order is this carbon silicon germanium and after this we have lead and then k okay this is the change we have and why this change is there because of again so we will have what greater attraction towards the nucleus and hence the difficult to remove electronegativity down the group you go electronegativity decreases write down next one oxidation state these elements can show plus 2 and plus 4 oxidation state elements with plus 4 oxidation state elements with plus 4 oxidation state behaves as oxidizing agent and with plus 2 it is reducing it same thing inert per effect the stability of plus 4 oxidation state decreases down the that's why plus 4 has to convert into plus 2 so get reduced oxidize others right write down the stability of plus 4 oxidation state decreases down the group plus 4 oxidation state decreases down the group and that of plus 2 oxidation state increases down the plus 2 oxidation state increases down the group and plus 4 decreases the reason is inert pair effect general characteristics of the compounds of group 14 elements general characteristics of the compounds of group 14 elements. The first one, first one is hydrides hydrides group 14 elements you know it forms covalent hydrides okay hydrogen we have discussed it right last class only that group first two elements like group boron forms electron deficient hydride boron family carbon form electron precise hydrides and all the other groups for electron okay so write down the elements of this group forms covalent hydrides of MH4 type we all know generally forms four types of compounds that is parafins which is alkene olefins which is alkene and acetylene which is alkynes and apart from that we have aromatic compounds also or four compounds carbon forms with hydrogen okay so next write down alkene's write down alkene's a weak bi bond a weak bi bond hence it can show addition reaction addition reaction and more reactive also we can say more reactive in comparison to alkene more reactive in comparison to alkene