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Compounds that have identical molecular formula but different chemical structure.

0
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1answer
35 views

Why is there only one ionization isomer of [Cr(NH3)5(NO2)]Cl2?

How many isomers are possible for $\ce{[Cr(NH3)5(NO2)]Cl2}$? Consider all possible types of isomerism and draw each isomer. My texbooks presents only three possible isomers: $\ce{[Cr(NH3)5(NO2)]Cl2}$ ...
9
votes
5answers
835 views

If a chiral molecule reacts with an achiral molecule will the product be chiral or achiral?

My book says that a pair of enantiomers will react the same way with an achiral substance. How is this possible? Does this imply that the product is achiral, even though the enantiomers are chiral? ...
2
votes
1answer
46 views

Number of spatial arrangements of tetrasubstituted biphenyl?

According to my book 2-bromo-2'-(1-chloroethyl)-6'-iodo-6-(prop-1-en-1-yl)-1,1'-biphenyl has eight possible spatial arrangements. How can this be so? I can think of only four – left two groups being ...
3
votes
1answer
57 views

Ortho vs para alkylation of chlorobenzene

I have a question to the solution regarding the product formed in a reaction with chlorobenzene with the use of (i) $\ce{CH3CH2Cl}$ and (ii)$ \ce{AlCl3}$. Since the -Cl substituent is ortho- para-...
-1
votes
1answer
32 views

why do the complex [Cu(NH3)5NO2]SO4 show ionisation isomerism?

In ionisation isomerism, secondary valencies can be replaced by primary valencies on the condition that net charge going outside the coordination sphere must be equal to net charge coming inside it . ...
0
votes
1answer
50 views

How are there only 8 structural isomers of C5H11Br?

Everywhere I see mentioned, that there are only 8 structural isomers of $\ce{C5H11Br}$. That is, the simple $\ce{C5}$ straight chain, $\ce{C4}$ with substituted methyl and $\ce{C3}$ with two ...
3
votes
1answer
40 views

Why do highly branched alkanes have higher octane numbers than their corresponding linear isomer?

The octane number of fuels are based on a set of primary reference fuels, which are mixtures of iso-octane and n-heptane. Now iso-octane being branched alkane has very less tendency to react and given ...
-1
votes
1answer
39 views

Why are some strucutres isomers while others are not? [closed]

Why are some structures considered isomers but others are not? Take C3H9N for instance, according to https://www.chegg.com/homework-help/questions-and-answers/four-constitutional-isomers-molecular-...
-1
votes
1answer
81 views

Explain optical activity in Biphenyl compounds

How is optical activity explained in biphenyl compounds using atropisomerism. NOTE: I was taught that if vertical symmetry exists then optical activity is not shown by any substituted biphenyl ...
0
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1answer
35 views

What are the metamers of penta-1,2-diene?

First of all, are there any metamers for dienes? If there are any, how can I find them?
7
votes
1answer
350 views

Are ortho, meta and para used in IUPAC nomenclature?

I was presented with the following question in an online test: To avoid any confusion, here are the arranged options: A. 2-Chlorotoluene B. 1-Chloro-2-methylbenzene C. B and D D. O-...
0
votes
1answer
72 views

Systematic Approach to Finding Number of Isomers [duplicate]

I have this compound I want to know how many isomers (including stereoisomers) may have this constitution. Is there a systematic approach towards solving such types of problems related to the total ...
0
votes
1answer
31 views

No.of isomeric ethers of formula C3H6O

I managed to get 3 ethers:- 1.4-member ring ether(Oxetane) 2.Vinyl ether 3. Epoxy ether This question was asked in my school exam and the teacher had given its answer as 4..Could anyone please tell ...
-1
votes
1answer
65 views

Number of total stereoisomers of a piperazine derivative

How do I find out the total number of stereoisomers of 3,6-dimethylpiperazine-2,5-dione? As far as I can see, the compound has two chiral carbons. Would the nitrogens make a difference? They seem ...
2
votes
0answers
58 views

Does dihydroimidazole show geometrical isomerism?

Does dihydroimidazole (above) exhibit geometrical isomerism? Does the fact that the lone pair is involved in conjugation with a double bond affect anything? As far as I know, it does not exhibit ...
12
votes
2answers
396 views

Number of stereoisomers of tetramethylspirononane

The above compound – 2,3,7,8-tetramethylspiro[4.4]nonane – clearly exhibits both optical and geometrical isomerism. The question is, how many stereoisomers does it have in all? As the number of ...
9
votes
1answer
185 views

Reactivity of different isomers of N2F2

$\ce{ N2F2}$ exists in two forms cis and trans. Today my chemistry teacher tells me that among the two only cis form takes part in reactions and that it is more reactive. But I have read elsewhere ...
0
votes
1answer
38 views

Is 3,4-diethyl-3-hexene cis or trans? [closed]

I'd really appreciate it if someone could explain this one, please! According to my answers sheet it is not cis nor trans. But it looks like it is cis? Why, according to my answers sheet, is this ...
0
votes
1answer
60 views

What is it meant by two different groups in stereoisomerism?

I understand there are some properties in an organic compound that allow stereoisomerism. double bond can't rotate two double bonded carbon atoms each have two different atoms or groups attached I'm ...
0
votes
0answers
91 views

Difference in alpha and beta glycosidic bonds [duplicate]

I have learned that the cellulose has a much rigid and orderly branched structure than the starch. However, the only significant difference between them is the different type of bond formed after ...
-3
votes
1answer
165 views

Structural isomers given a molar mass [closed]

How many structural isomers are possible for compound containing $\ce{C}$, $\ce{H}$ and $\ce{O}$ atoms only with their molar masses $100$ as well as the isomers are simultaneously ketones 3 ...
5
votes
2answers
493 views

Why are conformational isomers considered as isomers?

I was taught that geometric (cis-trans) isomers are considered isomers because there is a high energy barrier to breaking the double bond for rotation (to convert into the other isomer). Given that ...
-2
votes
1answer
119 views

Why dichlorobenzene doesn't show geometrical(cis/trans) isomerism? [duplicate]

As it has restricted rotation due to the presence of a double bond, it should show geometrical isomerism. Then, why doesn't it show cis/trans isomerism?
2
votes
1answer
112 views

Why is mer-AlQ3 more stable than fac-Alq3?

Several research papers and books say that the meridional isomer of tris-(8-hydroxyquinoline) aluminium is thermodynamically more stable than the facial isomer. What is the reason behind this ...
3
votes
0answers
99 views

Coordination isomerism variation

The school book and Wikipedia state that coordination isomers are: In a coordination isomer the total ratio of ligand to metal remains the same, but the ligands attached to a specific metal ion ...
-1
votes
1answer
147 views

Conditions for Chirality in optical isomerism [duplicate]

Is it necessary that any atoms which is chiral must have 4 different atoms around the central chiral atom(maybe it can be carbon if it's organic molecule) bonded to it? More specifically: I mean can't ...
4
votes
0answers
211 views

Hydration Isomerism in Cr(III) and Co(III) [closed]

Cr(III) and according to a paper I found also Co(III) are famous for the property called hydration isomerism. I already asked about how changes in the environment of a complex, for example temperature ...
0
votes
0answers
40 views

Structural isomers of tris(oxalato)chromate(III) [duplicate]

Draw all the possible isomers of $\ce{[Cr(ox)3]^3-}$ where $\ce{ox}$ is oxalate, the dianion of oxalic acid. Give the name of the type of isomerism involved in each case. Well I drew the two ...
3
votes
0answers
37 views

Which of the following is more stable?

In this image, does the arrows indicate correct rate of reactions? The upper arrow is longer and lower is shorter. According to me Chair is more stable than Twist Boat. Does axial and equatorial ...
1
vote
1answer
186 views

Why does dichloridobisethylenediaminecobalt(III) have only three optical isomers?

Sorry for the bad drawing and having $\ce{NH}$ instead of $\ce{NH2}$ In the first structure, the chlorine atoms are in trans position on the plane. In the second structure, the chlorine atoms are ...
5
votes
0answers
175 views

Why does the keto tautomer of guanine have lower energy?

Looking at the keto and enol forms of guanine, it would seem as if the enol form is more stable, due to the fact that aromaticity is established with the enol form. However, according to a question on ...
10
votes
1answer
141 views

How can a Hydrogen make such a difference?

Looking at familiar bodily fluids for a learning session. At first glance they both look the same. Then I noticed the N=C in biliverdin and HN-C in bilirubin. How can a N=C (imine group) and HN-C (...
3
votes
2answers
327 views

How are these two organic resonance structures different?

I've been working through some questions online (self study, not homework) predicting the various forms for molecules. One of the questions involved the following molecule (see image below). It had ...
4
votes
1answer
2k views

What is metamerism [duplicate]

According to metamerism in polyvalent functional groups, if both alkyl groups' around functional group are different then they are considered as metamers but in few books it is given that if one of ...
2
votes
2answers
529 views

Why does having identical groups on either side of the pi bond lead to no geometrical isomerism?

As far as I was taught, cis and trans isomers were categorised under stereoisomers and sub category of geometric isomers. Qualifying properties like, rigid and restricted double bond rotation (due to ...
1
vote
1answer
1k views

Are benzyl alcohol and o-cresol functional isomers or position isomers?

My textbook categorizes them as functional isomers (phenol and aromatic alcohol) whereas The above mentioned isomers are given as position isomers on 'chemguide.co.uk'
7
votes
1answer
160 views

Number of isomers in a 3-sugar oligosaccharide

I recently read that 12288 different oligosaccharides can be formed from the D-isomers of glucose, mannose and galactose. I wanted to try to calculate this, but I keep falling very short of this ...
-1
votes
2answers
259 views

How to determine if an alkene is an E or Z isomer?

Is the molecule below an E or Z isomer? From what I believe I would say E isomer because the two priority halides Cl and Br are on opposite sides of the double bond. But I'm not 100% sure. Because ...
1
vote
1answer
233 views

How many cis-trans isomers does 1-O-stearoyl-2-O-arachidonyl-phosphatidyl-inositol-4',5'-bisphosphate have?

I saw an exam that had a question asking the number of cis-trans-isomers of 1-O-stearoyl-2-O-arakidonyl-phosphatidyl-inositol-4',5'-bisphosphate: The "correct" answer in the exam is 1023, but this is ...
2
votes
1answer
8k views

Number of cyclic isomers of C4H6 [duplicate]

I faced a question How many cyclic isomers are possible for $\ce{C4H6}$? I and my friend found the following four. But the answer key says there are 5. So what's the other one?
4
votes
1answer
766 views

Dehydrobromination of 3-bromo-3-cyclopentylhexane and number of possible alkene products

I faced a question like this: The total number of alkene products possible from the dehydrobromination of 3-bromo-3-cyclopentylhexane is: The answer is given 5. But I only found 3. 3-...
0
votes
0answers
43 views

How do you predict isomers for certain hydrocarbons? [duplicate]

Hexane $\ce{C6H14}$ has 5 isomers, but I'm able to draw at least 6 different structures, which initially led me to think that there were 6 isomers. So how can I tell which structure will qualify as ...
1
vote
3answers
3k views

Are glucose and galactose cis-trans isomers of each other?

Glucose and galactose are diastereomers of each other. However, is it correct to say that they are cis-trans isomers of each other? Does it make a difference with regard to terminology if glucose and ...
1
vote
1answer
151 views

Difficulty in cis, trans isomers in Alkene [closed]

I have a difficulty in appointing cis trans isomer to an Alkene compound . I have looked it up and drawn out a few - Which "point" should I look at to understand in order to allocate cis and trans ...
0
votes
2answers
715 views

Monochlorination of 2-chloropentane and possible enantiomer products

I found a question to determine the number of possible chiral products of monochlorination of 2-chloropentane.So, first the products are (with possible number of enantiomers in the parentheses: 2,2-...
5
votes
1answer
239 views

Why does steric hindrance cause a d8 complex to have a tetrahedral geometry rather than a square planar geometry?

I'm currently working on a question based on two isomers of a nickel complex, where nickel exists in the oxidation state Ni(II) (i.e. has d-electron configuration $d^8$). It has been deduced that the "...
0
votes
1answer
667 views

Structural isomerism in iso-butyl and tertiary butyl alcohol

What type of structural isomerism exists between iso butyl alcohol and tertiary butyl alcohol? I think that there exists only positional isomerism between them but the source from where I am studying ...
2
votes
1answer
111 views

Stereocenter or not?

Consider 2,3,4-pentanetriol.Is the middle carbon atom a stereocentre?I know how to count the stereoisomers, but is the middle carbon a stereocentre by definition?Let us say we have a 2R and 4S ...
0
votes
1answer
68 views

Why is this molecule considered a cis isomer?

I know that we have two CH3 groups on one side and restricted rotation around the double bond but aren't we supposed to have two similar groups on the other side as well ? Does this mean that we only ...
-1
votes
1answer
203 views

Isomerism in amide and nitrile aldehyde

I have the following question, The given answer is c but I have trouble understanding why a would not be a correct answer. Because from my understanding in part a, one is amide functional group and ...