## heena 3 years ago qn :)

1. heena

in ur qn der will be 8 str.

2. shivam_bhalla

3. shivam_bhalla

@heena , Tip : don't make it linear

4. heena

ok and i got 8 str

5. heena

but here u see three bonds mean they are in same plane

6. heena

apoorv bhaiya jb tk shivam is posting or replying y dont u post qn for me ??

7. shivam_bhalla

It is @heena, E and Z for each bond

8. heena

hey par apne to pucha how many str is posible for GI y kb pucha k kya h yeh :/

9. shivam_bhalla

So combining many patterns like E,E,E E,E,Z E,Z,E E,Z,Z Z,E,E Z,E,Z Z,Z,E Z,Z,Z We get 8 as the answer . @hheena you are right. @apoorvk won't minding having a check

10. shivam_bhalla

*@heena

11. heena

wow apne str kese nikale? i mean combination ??

12. heena

and u knw its time consuming a lot :? dont try to evr to find it but nikala kese mje itna bta do bs :P

13. apoorvk

yeah you folks are right.

14. heena

i have only 15 mins :O at 6 i have to leve chem hour over :P

15. heena

so plz nxt qn or y combo kese nikala mene aj tj ni nikala :P

16. shivam_bhalla

@apoorvk bhai will give one :D

17. heena

kya arrey acha mje sirf combo btao kese nikalte h ?? baki mje ata h k str kese nikalte h :P

18. heena

heellloo koi kuch to bolo acha ek last qn do sbse tuff :)

19. heena

anyone plzzz :)

20. heena

i m going thank you for ur precious time :))

21. shivam_bhalla

@apoorvk, I will give you medal in advance for explaining :P

22. heena

lol selfish and lazy shivam :P mje ata h m to u hi puch rhi ti :P

23. apoorvk

Okay, let me post a 5 question test for you. Each question has one star at stake (if you get a question half right, you get half-a-star, and so on.) INSTRUCTIONS: For (1) state if a GI is possible and calculate the no. of GI's, if any. For (2-3) calculate the no. of POS in the structure. |dw:1337430444045:dw| 4. State if the the following contains any plane of symmetry, and how many if any. (a) A ceiling fan (three winged) (b) A screw. 5. Will the following compound have OI's?|dw:1337430262226:dw| You have 8 minutes - TIME STARTS NOW!

24. heena

ha vo to h par he is typin or not dunno anyways bye bye :P and apoorv bhaiya rhne do mje pta h y so dnt worry

25. apoorvk

Time is ticking...

26. shivam_bhalla

Tick tock tick tock...

27. heena

1- no GI 2 1 POS 3-1 POS both 2 and 3 have sasndwich 4-sandwich plane 5-no POS

28. apoorvk

4 has two parts.

29. heena

OI ni parha

30. heena

yea 4 k second part no POS

31. heena

by mistake i typed 5 point

32. apoorvk

what is sandwich POS? acording to you?

33. heena

sandwich uhhmm.. kese btao :O or cieling fan m sirf fan k wings le kr btana h na??

34. heena

say quick agr ceiling fan m wing k sat usk stalk bhit lena h to den it will have no POS

35. heena

and by POS i mean sandwich plane m present h :)

36. apoorvk

okay just calculate the POS in no. 5

37. heena

no POS in 5

38. apoorvk

sanwich means slice cut right? okay I get that.

39. heena

yea slice cut :) mje smj m ni a rha tha m bolu kese as not gettin any word to xplain :)

40. shivam_bhalla

heena ,good for all except first one. You first answer seems wrong to me

41. heena

may i knw my results plzz??

42. heena

y if u see the str shivam |dw:1337431264067:dw| if we try to cut it both the half will be different

43. apoorvk

Hmm Okay. Results time: 1 - ✘ 2 - ✔ 3 - ✘ 4(a) - ✘ (b) ✔ 5 ✔

44. apoorvk

Now now. Shivam will explain #1. The rest, I will.

45. shivam_bhalla

1 st one is wrong because of axial and equatorial isomerism is possible

46. apoorvk

if that's okay with you, Shivam?

47. shivam_bhalla

|dw:1337431392545:dw|

48. heena

wat is axial and equatorial isomerism? and @apoorvk y 4(a) is wrong?

49. heena

ok get it y 1 is wrong :)

50. heena

y 4(a) i wrong there is preence of sanwich plane so POS is possible :/

51. heena

plz quick ??

52. shivam_bhalla

@apoorvk , why 3rd one is wrong ?? There is only one PS as far as I can see

53. shivam_bhalla

*POS

54. heena

yea and reason for 3 too :P but first tell me abu 4(a)

55. shivam_bhalla

According to me, 4(a) has no plane of symmetry

56. heena

yea as xplained by u guys before 3 one i not havin POS :P

57. heena

there is plane of symmetery see the fan and if u cut it from sandwich plane u ll get eqauly half as mention only wing

58. shivam_bhalla

Sorry. Didn't realize that. IN that case you will have 3 plane POS for 4(a)

59. heena

|dw:1337431781756:dw|

60. heena

xactly :O my ans 4 (a) is right (:

61. shivam_bhalla

Wait. Let's hear @apoorvk 's point of view.

62. heena

apoorv y dint u tel us the reason ?? liten i dont have much time to wait for ur ans :/

63. apoorvk

A fan blade actually looks like this http://ars.sciencedirect.com/content/image/1-s2.0-S0378778811001435-gr6.jpg therefore no POS

64. shivam_bhalla

OMG @apoorvk , that is too much :P

65. heena

yea it is but new thing for me nice qn :) :) i ll ask thi qn to my ir deifinitely :D :D

66. shivam_bhalla

But nonetheless, pretty interesting question :)

67. heena

thnQ bhaiya and nw confirm wala bye and bhaiya plz blue aye to bta dena :)

68. apoorvk

as for #3, cyclopentane actually is a symmetrical molecule - all angles are equal. so it has 6 POS actually.|dw:1337432051112:dw|

69. heena

told u der is slice :/ : /

70. shivam_bhalla

@apoorvk , you should have mentioned the word cyclopentane :/

71. heena

anyways thnQ for the qn paper and i get the reult mje cyo qn p dhyan de kr jana hoga :P m bhut silly mitake kr ri hu usme hmm....

72. heena

*cylco=cyo

73. apoorvk

That structure can only mean cyclopentane - it is a way to trick students (considering that the figure drawn is never exact actually)

74. shivam_bhalla

@apoorvk , just kidding. But very careful and thoughtful questions @apoorvk :)

75. shivam_bhalla

Thanks for this chem-o-organic quiz :D

76. heena

but apoorv i m till confuse how POS present in it :? i mean cyclo pent afr hm str dekhe to spr hybrdised h or a i shown jb cut krenege to equal ni mil rha :O

77. heena

sp3 hybridised h sb

78. apoorvk

|dw:1337432418449:dw|

79. shivam_bhalla

what does slice mean ??

80. heena

i dont find any POS here if we cut sandwich or in any way as u shown it not correct |dw:1337432528787:dw|

81. apoorvk

Hmm.. that makes me think - yes you're right - I dunno what I was thinking. Yes, then there would be just 1 POS - from the mid (not sandwich)- Silly me.

82. heena

slice mean sandwich

83. shivam_bhalla

You mean cutting along the plane of cyclopentane ?

84. heena

1 POS no there is no POS see carefully once again plzz if we cut in sandwich too there will be up and down H not in same side

85. apoorvk

|dw:1337432620888:dw|

86. apoorvk

3-D lateral view - try to visualise that.

87. heena

that the xact str i thought wen i was answering suddenly dunno wat happens to me i get agree wid u :O really kitni bhudhu hu m :O yes 1 POS is there :)

88. apoorvk

me too - the asker himself is wrong :/

89. heena

hmm.... ehnce proved i hate organic :D

90. heena

*hence

91. shivam_bhalla

OMG, I love organic but I can never find the right answwer :P

92. shivam_bhalla

@heena , well done. Good enough for organic. But @apoorvk no need to be said. You gave awesome questions @heena , best of luck for tomorrow's exam

93. shivam_bhalla

94. apoorvk

All the best heena.

95. heena

@apoorvk how many POS is posible in the str.? |dw:1337499005255:dw|

96. heena

:'( mene aj bhut -ve kr li :O khushi khushi m :'( :'(

97. apoorvk

I think this will be zero - because the surrounding cyclo-propane rings are not in plane exactly, they are tilted at a some angle because there is enormous steric-repulsion from the other cyclo-propane groups. yes, I say '0'.

98. apoorvk

Don't worry, resolve the paper and check you mistakes.

99. heena

bhaiya u aid fan k wings or is str m kya difference h?? dono m POS ni honi chiye na y qn aya tha or my fan k str imagine krk zero tik kr di jbk ans galaat h :O :O

100. heena

mene paper solve kr liya tbhi to bol ri hu :'( meri rank pta ni kya hoga or aj to dad ne meri rank list mangai h :(

101. apoorvk

th fir answer 3 hai kya? yes bilkul sahi socha - this is like that fan blade thing

102. heena

ni ans 2 h :(

103. heena

bhaiya mene galat kr diya or rank list al a jayegi jime bhut -ve k h mene mje bhut darr lag rha h :'(

104. apoorvk

Don't worry it's only a eview test - aur bahut se test honge and what matter is the finals - abhi saare mistakes kar lo - baad mein mat karna simple :) And is question mein mujhe lagta hai ki: ek secondary ring primary ring ke plane mein hoga and baaki do perpendicular - tabhi answer 2 ho sakta hai - otherwise I feel ki they posted it wrong.

105. heena

mje ni pata kal jb paaper dicuss hoga to pta chl jayega and u knw mene ephli br around 20-ve kiya h or dad voi rank lit dekhna chte h agr unhone dekha 20-ve mje bhut darr lag rha h :'(

106. apoorvk

Don't worry maine kya bola - ab aage ki socho, jo ho gaya, ho gaya,

107. apoorvk

delete?

108. heena

bye .. ttyl

109. apoorvk

nvm

110. apoorvk

bye