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Chemistry: Post your doubts here!
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It means that different samples of the substance might have different melting points ... so basically it has a range of melting points ...
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is the answer A?
yes how?
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It has the most number of C-Cl bonds which persist high up in the atmosphere and break to form chlorine free radicals that deplete the ozone layer ... C-H bonds will break sooner once released into the atmosphere ... and C-F bonds are stable so they dont break as easily.
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Oh hahaha I didn't know polyethene did that
thnks
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different samples of polymers can have different no. of monomers to make it up ... the longer the chain, the greater the melting point .... thus the rangeOh hahaha I didn't know polyethene did that
no problemthnks
different samples of polymers can have different no. of monomers to make it up ... the longer the chain, the greater the melting point .... thus the range
no problem
Bro how to solve Oct nov 2014 Q 30 plz
http://maxpapers.com/syllabus-materials/chemistry-9701-a-level/attachment/9701_w14_qp_11/
My answer is 8
though its not in the marking scheme- Messages
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Can You help me with number 39 & 40?
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Bro how to solve Oct nov 2014 Q 30 plz
http://maxpapers.com/syllabus-materials/chemistry-9701-a-level/attachment/9701_w14_qp_11/
My answer is 8
See, the molecule given has a lot of C=C bonds ... but only the tertiary alkenes will oxidise to give ketones ... (the secondary alkenes will oxidise to give aldehyde which further get oxidised to form acids. The primary ones give CO2) ... tertiary alkenes is when a C in the C=C double bond is attached to 3 other Carbon atoms ... if u look at the molecule carefully, u will see that there are 6 tertiary alkenes.
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and oh! i am a girl
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only the 39th question is in the picture ...
Is the answer B? If so, then ...
alkaline (NaOH in this case) hydrolisis of ester has 2 products: the sodium salt of the acid and the alcohol ...
and the first part of the molecule where the C is double bonded to O becomes the salt of acid ... the other part becomes the alcohol.
Thanks
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40th question ... is the answer D?
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How +2??
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Reaction of aldehydes with HCN require Reflux OR it occurs at RTP?
Help Please!!!
Use of the Data Booklet is relevant to this question. Sir Humphrey Davy discovered boron, calcium, magnesium and sodium. Which of these elements has the second smallest atomic radius in its group and the third lowest first ionisation energy in its period?
A boron
B calcium
C magnesium
D sodium
The Ans is C
Use of the Data Booklet is relevant to this question. Sir Humphrey Davy discovered boron, calcium, magnesium and sodium. Which of these elements has the second smallest atomic radius in its group and the third lowest first ionisation energy in its period?
A boron
B calcium
C magnesium
D sodium
The Ans is C
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I think it its C.