okay class today we are going to discuss the CCD one of IOP and that CCD has 10 question that we are going to discuss today the first question is in homologus series if you talk about homologous series and omoga series what is same the general formula remains same as you know if I talk about alken in alken this general formula is CN H2N +2 for alken it is CN H2N so molecular formula is going to change as you go forward and increase the number of carbons next is secondary hydrogen atom so for that you Draw the structure first that is going to look like this ch3 C this is CH then it has two CH3 CH2 C2 H5 means CH2 CH3 make it like this otherwise you will get incorrect answer now secondary hydrogen atom so basically whatever secondary carbon and whatever hydrogen it has is known as secondary hydrogen so as you can see this and this is a secondary carbon okay so this secondary carbon because it is bonded to two carbons this is also bonded to two carbons so two secondary carbons hence four secondary hydrogens so answer is four next is secondary carbon atoms in methile cyclopropate car secondary carbon means that is bonded to two so if you see here this is bonded to 1 2 3 so this one is tertiary if you see for this one it is bonded to only one this is primary this carbon bonded here and here so secondary bonded here here so secondary okay so the correct answer is answer two next is only the primary and tertiary carbon so primary means this one is bonded to one carbon so primary similarly this one primary this one you see it is bonded to two carbon secondary similar it is bonded to two carbons secondary this is also bonded to two carbon secondary similar if you see here it is bonded to one carbon primary bonded to one carbon primary this carbon this is bonded to three so tertiary this is bonded to two secondary this is bonded to one primary this one is bonded to four carbons hence it is quartinary all these carbons are going to be brimly as it is only bonded to one one carbon each here if you see bonded to one carbon so one degree bonded to one carbon so one degree this is bonded to three carbons here here so 3° this is bonded to three carbons 3° this is bonded to one carbon 1° 1° this only has two 3° carbons and four 1°ree carbon so this is the correct option next one is which of the following is not an alicyclic compound alicyclic means when we talk about cyclic compounds cyclic compounds are distributed into alicyclic and aromatic right so if I talk about alicy that means whatever that is not aromatic is alicy so this is alicy this is aliccyclic this is also alicyclic even though it is hetrayy but still it is alicyclic this one is aromatic so this is the correct option next one is here what they asked is unsaturated hydrocarbon so they have written hydrocarbon means only hydrogen and carbon will be there unsaturated means having double bond or triple bond so this has double bond but it is hetroat atom this also has a double bond and triple bond but it is a hetroatom here there is no double bond or triple bond in this one there is a double bond between carbon and carbon only that's why this is the correct option next one you see here is how many secondary carbons are there secondary carbon means that is bonded to two carbons if you see here this carbon is bonded to one carbon here this carbon is bonded to two carbons this carbon is bonded to again two carbon this carbon you see it is bonded to three carbon here here here so 3° this carbon is bonded down here up here secondary this carbon is bonded to three that is tertiary and this is primary primary if you see here it is secondary bonded to two carbons this is also secondary bonded to two carbon this is primary bonded to one carbon so total 1 2 3 4 5 so it is answer is five now if I'll talk about you get my double bond equivalent double bond equivalent is calculated by two ways one is when structure is given or one way when molecular formula is given when molecular formula is given you calculate by C + 1 minus C means number of carbons minus number of hydrogen plus hydrogen minus number of nitrogen by 2 so carbon is four so 4 + 1 minus number of hydrogen is 6 6 + 0 - 0 by 2 so this is 5 - 3 that is 2 so correct answer is two how many sigma bonds are there in this number here the common mistakes everyone does is just see this thing that there are six sigma bonds present sigma bonds means single bonds so you can see six sigma bonds and you mark this answer but that is not correct because here this is bond line structure hydrogens's are missing so you have to draw hydrogens's also the moment you draw hydrogen's you will see there are many sigma sigma bonds more that was there now if you calculate the sigma bonds it would be six there 7 8 9 10 11 12 13 14 15 16 17 18 so correct answer is 18 actually next one is degree of unsaturation i told you when structure is given you calculate by this number of pi bond plus number of rings when molecular formula is given you use that formula that we just did so number of pi bonds plus ring so you can see this is one ring second ring then you calculate the pi bond so this is one pi bond one pi bond there are two pi bonds here in the alkine two pi bonds in the alkine total gives you eight okay so the answer is eight for this one okay