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Chemistry: Post your doubts here!

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should
Could someone please answer 2011 May/June Paper 12 Question 35. The mark scheme says the answer is A but the same question is in 2008 May/June(Question 36) and the answer there is C.

Thanks.
Should be C, 2 and 3.
1 is obviously wrong, N is being reduced. The oxidation no. changed from +3 to 0.
2, and 3 are correct. NaClO is a bleach and AgCl (precipitate will form)
 
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shoudn't it be 107? then how is it B?:sView attachment 54675
This is due to electronegativity of N > P. Detail explained here:¬
http://www.meritnation.com/ask-answ...mical-bonding-and-molecular-structure/1061393
Basically, answer is not 104 as well... Its just less then 109 degrees... so option here is give 104 so that is correct... if it was 107 given and 104 you should know 104 is the correct choice.. 90 and 104.. 90 is the correct and nearest degree..
 
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This is due to electronegativity of N > P. Detail explained here:¬
http://www.meritnation.com/ask-answ...mical-bonding-and-molecular-structure/1061393
Basically, answer is not 104 as well... Its just less then 109 degrees... so option here is give 104 so that is correct... if it was 107 given and 104 you should know 104 is the correct choice.. 90 and 104.. 90 is the correct and nearest degree..
You mean I should chose 104 instead 107? if 107 was given as an option ? :O
 
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The Sarcastic Retard qwertypoiu I need help in this question ...

Here i have posted the link for the question paper and my doubt is in question no 21 ....
I have even posted the explanation for Q21 which was answered previously .... My doubt is I don't get what they are trying to say in the part where i have highlighted ... so can one of you clarify it to me further.. Thanks in advance

https://docs.google.com/viewer?a=v&...sLm9yZ3x0ZWFjaGVyc3xneDoxYmI0OTYwOWIyZDRmNWVj

If the compound was an alkane and had no rings or double bonds, number of H atoms present = 2n+2 = 2(20)+2 = 42

Now, every time there're 2H less, you'll either have a double bond or a ring. The question states that there's one aldehyde (C=O) and 1 ring structure which has 1 C=C so this accounts for 6 missing Hydrogens, thereby leaving you with 8 missing Hydrogens.

8/2 = 4 Hydrogens in the aliphatic side chain.

However, total C=C are 5 because you have to include the C=C from the cyclohexene + cis formation hence A
 
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The Sarcastic Retard qwertypoiu I need help in this question ...

Here i have posted the link for the question paper and my doubt is in question no 21 ....
I have even posted the explanation for Q21 which was answered previously .... My doubt is I don't get what they are trying to say in the part where i have highlighted ... so can one of you clarify it to me further.. Thanks in advance

https://docs.google.com/viewer?a=v&...sLm9yZ3x0ZWFjaGVyc3xneDoxYmI0OTYwOWIyZDRmNWVj

If the compound was an alkane and had no rings or double bonds, number of H atoms present = 2n+2 = 2(20)+2 = 42

Now, every time there're 2H less, you'll either have a double bond or a ring. The question states that there's one aldehyde (C=O) and 1 ring structure which has 1 C=C so this accounts for 6 missing Hydrogens, thereby leaving you with 8 missing Hydrogens.

8/2 = 4 Hydrogens in the aliphatic side chain.

However, total C=C are 5 because you have to include the C=C from the cyclohexene + cis formation hence A
Sorry, no time : https://www.xtremepapers.com/commun...st-your-doubts-here.9859/page-381#post-745892
 
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Can someone please explain these:
MJ 14/11 Q8, 13, 34. Thank you.
 

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Is there any good website for Chemistry P1 solutions? I have found a youtube channel though "Meta Tutor"
 
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Is there an easier way to find out the number of isomers? and for this question how many are there?? Please help!!

It's 9701/13/0/N/14
 

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