Questions tagged [isomers]

Compounds that have identical molecular formula but different chemical structure.

Filter by
Sorted by
Tagged with
2
votes
1answer
30 views

How many ether metamers are possible for C4H10O?

How many ether metamers are possible for $\ce{C4H10O}?$ According to me, the answer should be 2 but it was given 3. I know 3 structures can be made: $$\ce{CH3—O—CH2—CH2—CH3}\tag{1}$$ $$\ce{CH3—CH2—...
1
vote
0answers
18 views

How would you order alkyl groups of this compound numerically? [closed]

If akyl groups are ordered alphabetically and ethyl comes before methyl, would this compound be called 2-ethyl-3,4 dimethyl pentane? Since that would be less than 4-ethyl-2,3 dimethyl pentane, correct?...
2
votes
0answers
41 views

Number of stereoisomers of polysubstituted cubane

The molecule given below is a substituted cubane. a) How many stereoisomers exist for this molecule? b) How many pairs of enantiomers are possible? How do I calculate the number of ...
0
votes
3answers
62 views

Identify the type of structural isomerism

Question: My Approach: Since both the compounds have the same principal functional group, they can't be functional isomers. Obviously they are different compounds. Now options A and C are ruled out. ...
0
votes
1answer
38 views

Doubt in conditions for geometrical isomerism

In my textbook, under the topic "Conditions for geometrical isomerism", the following has been given: Groups responsible to show geometrical isomerism must be nearly in the same plane. Is this ...
1
vote
0answers
44 views

Finding structural isomers of an alkene

I am doing problems on finding structural isomers. I am asked to find the structural isomers of $\ce{C5H10}$. The answer to problem states there are 10 structural isomers possible. I was able to find ...
0
votes
0answers
26 views

Plaster of Paris

One of my Chemistry professors said that the hard mass formed after adding water to Plaster of Paris, cannot be converted back into Plaster of Paris. However, he said that the original Gypsum can be ...
0
votes
1answer
14 views

Are these chemical reactions with amino acids possible, and if so, what are they called?

In high school, I am taught that the synthesis of two amino acids of the form $\ce{H2NR1COOH}$ and $\ce{H2NR2COOH}$ is a condensation reaction that produces a polypeptide $$\ce{H2NR1COOH}+\ce{...
0
votes
1answer
55 views

Doubt in isomerism

Question Give isomeric relations between these compounds. My answer A and B show metamerism and positional isomerism. A and C show chain isomerism and metamerism. B and C show chain ...
4
votes
1answer
51 views

Which is the correct definition for metamers (or metamerism)?

I have heard two definitions of metamers. Compounds having the same molecular formula but different number of carbon atoms on either side of the functional group. Compounds having the same molecular ...
0
votes
1answer
57 views

What are the isomers of a complex having a structure of M(AB)2C2?

Our instructor have us answer an isomerism problem of a crystal structure that has a form of $\ce{M(AB)2C2}$. I keep getting 9 isomers, which includes the optically inactive isomer, and my peers and I ...
1
vote
1answer
248 views

What is the total number of isomers, considering both structural and stereoisomers of cyclic ethers with the molecular formula C4H8O?

According to me, it should be 11 and this is how I have worked out as shown in the attached diagram. However, I am not sure whether all these 11 isomers can be considered as those belonging to ...
3
votes
0answers
73 views

Which is more stable: isobutylene or cis-2‐butene?

How do you compare which is more stable without using the heat of hydrogenation or combustion or any other numeric factual value: $\ce{(CH3)2-C=CH2}$ or $\ce{CH3-CH=CH-CH3}$ (cis)?
5
votes
1answer
114 views

The maximum no. of isomers (including stereoisomers) that are possible on mono-chlorination of the compound: 3,3-dimethylpentane is?

The maximum no. of isomers (including stereoisomers) that are possible on mono-chlorination of the compound: 3,3-dimethylpentane is? The answer given is 5. My working: The fourth carbon is chiral ...
1
vote
1answer
71 views

How do we know if this following molecule is a superimposable mirror image or non-superimposable mirror image ? [See Image attached]

How do we know if this following molecule is Super Imposable mirror image or Non Super Imposable mirror image ? [See Image attached]
-2
votes
2answers
107 views

Which of the following compounds is NOT an isomer? [closed]

Which of the following compunds is not an isomer? I cant figure out how the answer is d
1
vote
0answers
61 views

Why do tetrahedral organic molecules show stereo-isomerism, but not tetrahedral transition metal complexes?

Both types of molecules show different arrangements of the molecule in space, so they should qualify for optical isomerism right?
-1
votes
1answer
69 views

Confused between structural isomers versus stereoisomerism

So this question wanted me to find two cyclical compounds that are 'structural' isomers of the molecular formula given in the question. The two isomers I came up with are: 1,2-dichlorocyclopropane ...
2
votes
1answer
45 views

Cis and Trans Isomerism given three different groups around the reference plane

In the following problem I am meant to deduce the molecules that are cis-trans isomers of each other. This question does not make much sense in my head because I thought that cis/trans isomerism was ...
0
votes
1answer
50 views

What is the name of “cis/trans” isomerism when all four groups are different?

How would you call a pair of isomers on the picture below? They look a lot like regular cis/trans isomers, except all four groups are different. I can tell they are spacial isomers (stereoisomers) ...
-1
votes
1answer
22 views

Interchangeable isomers [closed]

I am a clinical research professional. I have a question regarding clinical chemistry. I would like to know that whether it is possible to get testosterone undecanoate from ursolic acid and vice-versa ...
1
vote
0answers
32 views

The van't Hoff rule for stereoisomers with planes of symmetry

We know that the maximum possible numbers of stereoisomers of a molecule is given by the van't Hoff rule, which says that: $$Total \space stereoisomers = 2^{n}$$ Where $n$ is the number of ...
2
votes
0answers
40 views

What does the dissociative mechanism for cis/trans interconversion of [Mo(CO)4(PPh3)2] look like?

All I can find in the literature is that the cis→trans interconversion proceeds via dissociation of one of the PPh3 ligands resulting in a square-pyramidal Cs intermediate, with the remaining PPh3 in ...
9
votes
3answers
294 views

Why are carbons of Inositol chiral centers?

I was asked to draw all possible stereoisomers of inositol (1,2,3,4,5,6-cyclohexanehexol). To obtain the answer I had to assume that all six carbons of the molecule are asymmetric, which (bearing in ...
6
votes
2answers
219 views

Melting point of unsymmetrical dimethylhydrazine vs 1,2-dimethylhydrazine

Unsymmetrical dimethylhydrazine ($\ce{H2NN(CH3)2}$) has a melting point of −57 °C, but its isomer, 1,2-dimethylhydrazine ($\ce{(CH3NH)2}$) has a melting point of −9 °C. That looks to me like a ...
1
vote
0answers
54 views

ionisation isomers [closed]

With ionisation isomers, how do you know which ligand (out of $\ce{Br}$ and $\ce{NH3}$ for example) exchanges with the compound outside the bracket?
-1
votes
1answer
32 views

isomerism-position versus chain

For nitriles carbon of nitrile group is part of the carbon chain. So what is the isomerism shown by pentanenitrile and 2-methylbutanentrile? Chain isomerism or position isomerism?
1
vote
1answer
363 views

number of optical isomers of a cyclic molecule

What is the number of optical isomers for this compound? Also, there seems to be no clear-cut boundary between geometrical isomers and optical isomers. Referring to a post in StackExchange, is (RS)- ...
0
votes
1answer
79 views

Can anyone tell me what reaction is this?

I came across this reaction, but I have no idea what reaction is this. Can anyone please tell me? What will be the products? My first guess is that a carbene will be formed which will attack on the ...
3
votes
1answer
250 views

How many stereoisomers are possible for 1,2-dimethyl-4-(propan-2-ylidene)cyclopentane?

How many stereoisomers (not counting different conformers) does 1,2-dimethyl-4-(propan-2-ylidene)cyclopentane have? I think the answer should be 3. There are two geometrical isomers (cis and ...
2
votes
4answers
241 views

Total number of stereoisomers of 2,3,5,6-tetrachlorooctane

Total number of stereoisomers for: I tried the following combinations: RRRR, SSSS, RRRS, SSSR, RRSS, RSRS, SRRS, RSSR, RSRR, SRSS, RRSR, SSRS, SSRR, SRSR. So, total number of stereoisomers I ...
0
votes
0answers
201 views

Hydrate isomerism

My book specifically mentions in the solution to a question: $\ce{[CrBrCl2 (H2O) (NH3)2].H2O}$ is not the hydrate isomer of $\ce{[CrCl2 (H2O)2 (NH3)2]Br}$ But the author hasn't provided any ...
1
vote
1answer
255 views

Classification in Stereoisomerism [closed]

I was trying to understand stereoisomerism. I am having trouble creating a 'flow chart' of Stereoisomerism. While there are many sources available over the internet and books, I don't find a standard ...
-1
votes
2answers
486 views

Why does 1,3-dichloropropane not show stereoisomerism?

It is a multiple choice question: Which compound does not show stereoisomerism? A 1,2-dichloroprop-1-ene B 1,2-dichloropropane C 1,3-dichloroprop-1-ene D 1,3-dichloropropane I ...
1
vote
1answer
471 views

Are Anomers Epimers?

epimers are the class of stereoisomers which differ along configuration at any carbon in a carbohydrate(generally), And anomers are the kind of stereo isomers that differ at the carbonylic carbon, ...
0
votes
1answer
165 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: $\ce{[Cr(NH3)5(NO2)]Cl2}$ ...
10
votes
5answers
2k 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? ...
6
votes
2answers
148 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 ...
4
votes
1answer
588 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
164 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
498 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
668 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
123 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
965 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
votes
1answer
268 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
1k 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
137 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
142 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
168 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
169 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 ...