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Hi Ultima, may i ask you,
https://www.dropbox.com/s/1ytc70wi31pu11c/20160329_152652.jpg?dl=0
Will this molecule have pi e- cloud? Nt sure because not uniform atoms, alternating N and P atoms instead of only C atoms
Can Si potentially form at Y? Theoretically, it could right? As period 3 element has energetically accessible vacant d orbitals. Then N atom can donate dative bond to Si?
In this case, is it P is more likely than Si, because form single bond more natural than dative bond ah (idk)??
Thanks for your guidance.
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Hi sir, can enquire your help on this,
https://www.dropbox.com/s/5gyb09xdknrbuuz/20160329_154547.jpg?dl=0
How do siah??
My knowledge : all comparable mr. Water can form 2 H bonds per molecule.
My doubts : how to see if bond is more polar? (Option c)
Option C : why a more polar O-H bond (compared to N-H bond) will result in stronger H bonding?
Option B : how will this affect at all?
Can hydroxylamine form 2 Hbonds per molecule too? The molecular structure I've drawn,seems like there are plentiful H atoms with partial positive to form H bonds with
Thank you.
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What are the factors affecting strength of Hydrogen bonding?
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Hi ultima, may i seek god advice from this mindbending no link question,
https://www.dropbox.com/s/iq5aumnfaop0kay/20160329_164759.jpg?dl=0
Doubts : can assume all ions (aq) state?
How to know state symbol for just Cl itself?
How to solve this qn?
Free radical (e.g. ch3 or cl ) is in what state? Is it Gaseous ?
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Story damn shag bro
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Originally posted by Flying grenade:
Hi ultima, may i seek god advice from this mindbending no link question,
https://www.dropbox.com/s/iq5aumnfaop0kay/20160329_164759.jpg?dl=0
Doubts : can assume all ions (aq) state?
How to know state symbol for just Cl itself?
How to solve this qn?
In future, if u want me to reply u on the forum, post 1 qn at a time. Wait for me to reply 1 qn, b4 posting another. Don't blitzkrieg or carpet bomb or vomit out dozens of qns at a time.Answer is C. All state symbols are (glass) or (plastic), not (aq) or (g), because all the ions and atoms are embedded within the glass or plastic lens itself.
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Originally posted by Flying grenade:
Free radical (e.g. ch3 or cl ) is in what state? Is it Gaseous ?
Depends on the solvent used. If no solvent, then (g). If there's a solvent (eg. water or ethanol), then (aq) or (EtOH) or whatever solvent. If dunno solvent, use (solv). -
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Originally posted by UltimaOnline:
In future, if u want me to reply u on the forum, post 1 qn at a time. Wait for me to reply 1 qn, b4 posting another. Don't blitzkrieg or carpet bomb or vomit out dozens of qns at a time.Answer is C. All state symbols are (glass) or (plastic), not (aq) or (g), because all the ions and atoms are embedded within the glass or plastic lens itself.
Why C? For a moment i thought that cl is gaseous.
So that representation of Cu+ and Cl, they are both in the plastic state(embedded in the sunglass lens) ?
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So when halogen is added to alkene, it is the alkene nucleophile attacking the halogen electrophile to have a electrophilic addition reaction ah? (Since the more proper terms is only nucleophilic attack ah?)
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What are the factors affecting ease of Hydrolysis? Bond strength?
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U spamming qns again. Ask 1 at a time. Wait hours for me to reply 1 qn, then post the next qn. Or I won't reply any of them.
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Originally posted by Flying grenade:
So when halogen is added to alkene, it is the alkene nucleophile attacking the halogen electrophile to have a electrophilic addition reaction ah? (Since the more proper terms is only nucleophilic attack ah?)
Size matters. Smaller is added to larger. X2 is smaller (in terms of no of atoms in the molecule), alkene is larger. In both elementary steps of the mechanism, it's nucleophile attack electrophile. -
Originally posted by Flying grenade:
What are the factors affecting ease of Hydrolysis? Bond strength?
Depends on context. Hydrolysis of what? If C-X (Cl vs Br vs I), then yes. If acyl halides vs alkyl halides vs aryl halides, then look at sterics and electronics, which affect electrophilicity. -
Originally posted by UltimaOnline:
Depends on context. Hydrolysis of what? If C-X (Cl vs Br vs I), then yes. If acyl halides vs alkyl halides vs aryl halides, then look at sterics and electronics, which affect electrophilicity.Thank god
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Hi ultima, may i ask you,
https://www.dropbox.com/s/awd0smgdjlwwfsd/20160329_192327.jpg?dl=0
Can the double bond at the ring exhibit cis trans isomerism?
I cant visualise ):
Please advise if u could, thank you!
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Originally posted by Flying grenade:
Hi ultima, may i ask you,
https://www.dropbox.com/s/awd0smgdjlwwfsd/20160329_192327.jpg?dl=0
Can the double bond at the ring exhibit cis trans isomerism?
I cant visualise ):
Please advise if u could, thank you!
This ring is too small to have geometric isomerism about the alkene group. -
How to know if which double bond at a ring ,
or how to deduce the size of the ring,
Such that a molecule can exhibit geometric isomerism ?
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Originally posted by Flying grenade:
How to know if which double bond at a ring ,
or how to deduce the size of the ring,
Such that a molecule can exhibit geometric isomerism ?
Try googling this out for yourself, instead of me spoonfeeding you. Or better yet (Lol), ask your school teacher. See if he/she knows. -
Hi ultima, may i ask what other factors might affect this other than steric hindrance?
https://www.dropbox.com/s/2l6bxfaaarpk3wu/20160330_180801.jpg?dl=0
Qn part d)
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Ultima, may i ask u if cstoh chemistry study guide have steric hindrance? Tried finding ,flipped every page at the org chem section, cant find, index doesn't have steric hindrance also
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Originally posted by UltimaOnline:
Depends on context. Hydrolysis of what? If C-X (Cl vs Br vs I), then yes. If acyl halides vs alkyl halides vs aryl halides, then look at sterics and electronics, which affect electrophilicity.May i ask what do you mean by electronics?
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Nitration of methyl benzene occurs more readily than Nitration of benzene , because ch3 group donates e- into the benzene ring, hence making it more nucleophilic ah?
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Originally posted by Flying grenade:
Hi ultima, may i ask what other factors might affect this other than steric hindrance?
https://www.dropbox.com/s/2l6bxfaaarpk3wu/20160330_180801.jpg?dl=0
Qn part d)
Ultima, may i ask u if cstoh chemistry study guide have steric hindrance? Tried finding ,flipped every page at the org chem section, cant find, index doesn't have steric hindrance also.
May i ask what do you mean by electronics?
CS Toh's book is the basic H2 syllabus summary, so it may lack elaborative terms such as "steric hindrance" and "electronics". It's still a must-have book for all H2 students, but students intending to score A grade should also obtain further materials in addition (not in replacement) of CS Toh's book, see my BedokFunland JC's list of recommended books for H2 Chemistry :
http://infinity.usanethosting.com/Tuition/#Books_for_H2_ChemistryTertiary alkyl halides (such as in ur qn part d), undergo SN1, and primary alkyl halides undergo SN2, for 2 reasons : sterics and electronics.
Sterics and electronics are also the reasons why aldehydes are more electrophilic than ketones, so if you only have 1 mole of a nucleophile reacting with 1 mole of an electrophile with both aldehyde and ketone groups present, it is the aldehyde, not the ketone, which will be the electrophilic group accepting the nucleophile.
Electronics refers to the relative magnitudes and distribution of charges (both formal charges in resonance contributors and partial charges in resonance hybrids) as a consequence of either induction or resonance or hyperconjugation (the 1st 2 of which are more important for the H2 syllabus).