Finding Closo/Nido of Carborane alongwith Dodecahedron/Icosahedron - GATE 2017

[@prateekwadi6666]

but sir when to use 2ch=3bh and when to use c=bh ?? plz telll

[@bikramkesharisahoo5464]

We know CH is isolobal with BH2. But this hasn't been applied here. Why so? Can you explain when to apply which rule??

[@nenavathparvathalu5012]

2CH=3BH? 2*5=3*4 10=12? Sir how it is equal, can you please explain me. Thank you.

[@DibyaJyotiMondal]

you are absolutly right, how is this possible

[@akb0014]

Yaa.. Something is wrong

[@tapashkalita3528]

It is a formula. It is not wrong. Though i dont know how. But its true

[@shanmugapriya3318]

B atomic number 5 where as c 6....so for equalise

[@yogi5752]

it is absolutely correct Boron hydrogen bond contributes two electrons. Carbon hydrogen bond contributes 3 electrons. (That is in carboranes). So 2CH= 2*3=6 3BH=3*2=6

[@akb0014]

Ch3 donates one electron to skeletal structure

[@yogeshbhoir8411]

(Me)3C2B10H10= (H)2(BH)2 B10H10 =B12H14....closo...CH3 replace by H.....Same concept repeated somewhere net or gate ...Don't remember...Is it right ?

[@madihaaslam2173]

Dn't understand vertics

[@dishasingh5244]

how to calculate 2CHunit equal to3 BH unit ?

[@Surya_963-chem]

So much confusing is it...have seen that you had faced same problem on 3 yrs ago.. hope now itz clear to you...can you explain it mam ?🙏

[@pavithradoss7113]

Does not understand Vetices

[@myfamily4048]

Sir , please give the link of calculating no. of vertices.

[@shrddhachavan2879]

Sir not understood this question plz explain 2CH=3BH

[@gitasrikalita5577]

Sir can't we just replace the carbon by a BH unit..then the cluster type will be arachno..I may be wrong but sir I think there's something wrong with the calculation

[@AllBoutChemistry]

Yes you can do it like that as well, keeping Me as side chains

[@monishayadavhs1649]

Sir by replacing C with BH, we are getting Arachno. How is this wrong, since there's no option too?

[@charupiplani2624]

When i put c=BH den not find the same answer as trick u done C2B3H5 in which I put c=BH den find the answer"""plz clear my doubt

[@deepikamks]

Exactly ....i have the same doubt

[@paromitasasmal1050]

I have also that same doubt

[@chellapandians9767]

No of vertices = SEP - 1

[@dr.sonalimahule4101]

If CH3 gr is not a part of skeleton framework then why it is considered in calculating the TVE? Please explain

[@AllBoutChemistry]

Here I'm talking about how much electron it will donate to skeletal framework, that's why I didn't took 5 electrons for CH unit. CH donates 3 electrons to framework and BH donates 2 Thats why 2CH=3BH

[@bhaktaharinayak2002]

sir from which book I will followe that valuable for me and getting such things

[@AllBoutChemistry]

www.chemohollic.com/2016/06/complete-list-of-reference-book-in.html

[@dr.sonalimahule4101]

How the 2CH become 3BH ? would u please explain

[@AllBoutChemistry]

Read out comments I've answered it many a times.

[@bhaktaharinayak2002]

sir 2(c-H)=3(B-H) ,how

[@AllBoutChemistry]

See.. According to wade rules each CH unit contributes 3 electrons to the structure and each BH unit contributes 2 electrons. So, 3BH=2CH units. 3×2=2×3 electrons.

[@lakshmipediredla8153]

But in wade rule they said one carbon is equal to BH, you followed this in your wade rules, why not in this example

[@bhaktaharinayak2002]

initially I had a also doubt like you but then I found the answer 2(C-H)=3(B-H)

[@bhaktaharinayak2002]

initially I had a also doubt like you but then I found the answer 2(C-H)=3(B-H)

[@subhashinisamuel396]

Bhaktahari Nayak sometimes we take valence electron...BUT here u have taken electron contribution for CH ..how to know when to use which..pls explain.

[@PriyaTheChemistryGuru]

Sir if SEP = NO of vertices... In this qstn if IAM solving no. Of SEP I get 13 but as u said according to vertices it is 12 .. Can u plz explain it sir

[@AI1946-x3j]

sir what will be the dissociation energy of H2 molecule in eV if ground state energies of H atom (-13.6eV) and H2 molecule(-31.7) are given??

[@premprajapat5282]

Ch3 replace by H

[@pritismita7585]

Sir I couldn't understand the no of vertices part.. Kindly give Mora example regarding how to calculate no of vertices

[@AllBoutChemistry]

Priti Smita, this was just a problem solved.. I've made a video on Wade-Mingos rule... Kindly watch that... There I've discussed about number of vertices and all...

[@pritismita7585]

Sir I have already seen this video.bt there is no explanation about no of vertices. There is discussion about SEP. Is SEP = no of vertices

[@AllBoutChemistry]

yes the values given there for SEP is also showing number of vertices.

[@pritismita7585]

Ok..thank u sir

[@AllBoutChemistry]

You're welcome 😊

[@jbchemistry4984]

Sir will you please explain a little about the concept of 2CH=3BH

[@AllBoutChemistry]

Jolly Balel, When we talk about electrons contributed by a unit in skeletal system, then, one BH unit contributes 2 electrons whereas one CH unit contributes 3 electrons. This we can say 2CH=3BH as eventually we get 6 electrons in both cases.

[@noopurdeshmukh6985]

Sir plz give more examples of electron contribution of this nature.

[@bhaktaharinayak2002]

very nice explaination sir

[@monikathakur000]

Hlo sir kya hum is question ko valence e- count vale method se baat kar sakte hai?

[@goonjthevoiceinside7574]

Sir... I m admirer of ur video... You really doing a good job bt honestly speaking its sort of different or may b confusing for me to understand this as its different method.... As far as I knw there is a formula to predict skeleton pair..... bt still unable to solve questions related to skeletal pair for transition metal complexes....kindly upload more videos related to this topic.... Thanks

[@komalsavaliya7046]

sir, isme SEP find karke shape find nai par sakte ?

[@tapashkalita3528]

Sir,Here you r coverting Me group to Isolobal group. So only vertices will be from C2 and B10 in the formula.. Me group are not forming the vertices. I think in that you sir

[@shanmugapriya3318]

Dodeca mean 12 ...y u say for 8

[@bhaktaharinayak2002]

cH=5,BH=4 is it or not

[@AllBoutChemistry]

It's not about the number of valence electrons, it's about the number of electrons contributed in the structure, BH contributes 2 electrons and CH contributes 3 electrons

[@chemistrychannel978]

No metal is equal to vertices

[@subhraneelsamui]

Sir in isolobal video , you said CH is 5 , bt here how you are calculating CH is 3

[@AllBoutChemistry]

Here I'm talking about number of electron donated in the polyhedral skeletal framework of carborane. In case of Carborane only we have to use this method, When I said CH=5 that was number of valence electrons in it. Both the things are different. 👍

[@subhraneelsamui]

Ok sir, how you calculating CH 3 , BH 2 , or we just have to remember,

[@AllBoutChemistry]

No these are known values and you've to remember them.

[@saumyasharma6762]

According to wade' s rule CH gives 3

[@zchemistry4435]

Its 5....4 frm c and 1 frmH

[@Real-intertainment726]

PEC=TVE-2n (n=b+c) n =no. of vortices PEC/2=skeletol eletron pair. =13=(n+1) closo. this mangos rule for carborane

[@venkatesh267]

What is PEC

[@chemwisdom8388]

(PEC)Poly electron count

[@shikhadhakar3296]

2 CH= 3BH ...How..??

[@AllBoutChemistry]

It's not about the number of valence electrons, it's about the number of electrons contributed in the structure, BH contributes 2 electrons and CH contributes 3 electrons So it's 2×3=3×2 electrons

[@shikhadhakar3296]

All 'Bout Chemistry sir but how will we know where to use this bcoz we usually write cH = BH2