Hi ultima here is my qns thanks (qns 19)
https://www.instagram.com/p/BDYWkk8yTaE/?taken-by=mightybiscuits1
Originally posted by MightyBiscuits:Hi ultima here is my qns thanks (qns 19)
https://www.instagram.com/p/BDYWkk8yTaE/?taken-by=mightybiscuits1
1stly, ur image only has Q20 & Q21, no Q19.
2ndly, don't just upload the question, but you must also give your own attempted solution or working, describe thought process, or ask specific queries or doubts. I'm not gonna do your homework for you and give you full complete worked solutions, I'm here to give you guidance on your thought process and on relevant concepts underlying the question.
So re-upload Q19, and be specific in which part of the question, and in which way, you need guidance on. Don't just say, "totally dunno how to do, help!". Like that must ask face-to-face during tuition liao, cannot use forum.
P.S. If you've the answers or solutions to your question (eg. your school's tutorial qns), upload them as well. Then ask me exactly what about the answer or solution you don't understand. The image above is from CS Toh's Practice Qns, where full worked solutions are provided. So what exactly about Q19's worked solution that you don't understand?
Oh sry i didnt notice.
https://www.instagram.com/p/BDYfruSSTTz/?taken-by=mightybiscuits1 (qns 19 ans)
https://www.instagram.com/p/BDYfnpkSTTl/?taken-by=mightybiscuits1 (qns 19)
I dont understand what is the meaning of hydrolysed. Does it mean that it is water of crystallisation? And whats the difference between hydrogen chloride and hydrochloric acid.
https://www.instagram.com/p/BDYfruSSTTz/?taken-by=mightybiscuits1 (qns 19 ans)
https://www.instagram.com/p/BDYfnpkSTTl/?taken-by=mightybiscuits1 (qns 19)
Originally posted by MightyBiscuits:Oh sry i didnt notice.
https://www.instagram.com/p/BDYfruSSTTz/?taken-by=mightybiscuits1 (qns 19 ans)
https://www.instagram.com/p/BDYfnpkSTTl/?taken-by=mightybiscuits1 (qns 19)
I dont understand what is the meaning of hydrolysed. Does it mean that it is water of crystallisation? And whats the difference between hydrogen chloride and hydrochloric acid.
Hydrolysis (noun) or hydrolyze (verb) or hydrolyzed (adjective), refers to chemical reaction with water. If you ask your school teacher or other private tutors or websites, a lot of them will tell you it means 'water-splitting' (hydro-lyze), but it could be either water or the other reactant, or both that is being lyzed or split, so "chemical reaction with water" is actually a superior definition, in terms of chemistry concepts. In this question, germanium chloride reacts with water to generate germanium oxide.
Hydrogen chloride refers to HCl(g) or HCl(l), while hydrochloric acid refers to HCl(aq), which is actually hydroxonium chloride, ie. H3O+(aq) and Cl-(aq).
Ok i understand already thanks
Hi Ultima,
May i ask,
Reason for trans isomers having higher MP than cis isomers : trans isomers pack better than cis isomers. More effective IMF, more energy reqd to overcome IMF hence higher MP
Reason for Cis isomers having higher BP than trans isomers : Cis are polar, trans non polar.
Can the above reason apply for Melting point of cis-trans isomers?
If so, then is it that the factor of better packing of trans outweighs the factor of polarity of the cis-trans isomers, in the case of melting ? (Since cis being polar may suggest cis have higher mp, compared to the effect of better packing of trans)
Ultima, may i ask u,
https://www.dropbox.com/s/pf5n38793wj8irm/20160326_124915.jpg?dl=0
The picture above DHS 2014 qn, states that polar protic solvents contains at least one H atom directly bonded to an electronegative atom.
From wiki : any solvent that contains labile H+ is called a protic solvent. The molecules of suchsolvents readily donate protons (H+) to reagents.
But, why will the electronegative O or N readily donate the H+??
Hi Ultima, may i ask u,
From wiki : Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula (CH3)2SO. This colorless liquid is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water.
Since this polar compound can dissolve both polar and non polar cpds, the rule of thumb adage 'like dissolves like' , not really true?
Update : DMSO is partially polar, partially nonpolar.
And 'like dissolves like' is a oversimplification
Polar aprotic is weakly polar, Polar protic is strongly polar right?
Originally posted by Flying grenade:Polar aprotic is weakly polar, Polar protic is strongly polar right?
Hi Ultima, may i ask ( and help check correct wording/terms too)
Why sp (hybrid) orbital contains 50% S character, 50% P character?
Sp2 contains 1/3 s character, 2/3 p character?
Sp3 1/4s character, 3/4 p character?
Why for sp3, no pi bond formed ( tetrahedral molecule with 4 single bonds ) have p character? ?
Originally posted by Flying grenade:Hi Ultima, may i ask ( and help check correct wording/terms too)
Why sp (hybrid) orbital contains 50% S character, 50% P character?
Sp2 contains 1/3 s character, 2/3 p character?
Sp3 1/4s character, 3/4 p character?
Originally posted by Flying grenade:Why for sp3, no pi bond formed ( tetrahedral molecule with 4 single bonds ) have p character? ?
Instagram.com/p/BDcx4P6yTaJ/
(the question on top)
Please help solve and explain why.
Originally posted by WILLYNILLY:Instagram.com/p/BDcx4P6yTaJ/
(the question on top)
Please help solve and explain why.
Originally posted by UltimaOnline:
Because of simple math.
Yes , thank you! I finally fully understand how hybridisation works already. Grateful (:
I also wrote out the electronic configuration of the 4 thing but I dont know how it leads to C or D
Originally posted by WILLYNILLY:I also wrote out the electronic configuration of the 4 thing but I dont know how it leads to C or D
Ultima, may i ask,
Wouldnt the N,N,N naming of amines be ambigious e.g. different substituent for two different compounds, but same name??
Originally posted by UltimaOnline:
First of all, nothing "forms" at the benzylic C atom, wrong choice of words.Secondly, your reasoning is totally wrong (ie. it's not about electronegativity of O vs Br, because even if it was fluorine used instead of bromine, and F is of course more electronegative than O, the major and minor products discussed above will still be similar, albeit with *additional* possible beyond-H2-syllabus products due to the strongly oxidizing and highly reactive nature of fluorine).
Draw the full mechanisms to get both major & minor products (actually, there'll be a total of 3 possible products excluding stereochemistry when using aqueous halogen, can you figure out why?), and upload the image.
Note : many Singapore JCs teach wrongly that OH- attacks the carbocation, but it is actually H2O that is the competing nucleophile. Don't make this error in your mechanism.
Is it br and oh,
Oh and br,
And oh , oh?
Originally posted by Flying grenade:Ultima, may i ask,
Wouldnt the N,N,N naming of amines be ambigious e.g. different substituent for two different compounds, but same name??
Originally posted by Flying grenade:Is it br and oh,
Oh and br,
And oh , oh?