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In one molecular structure, the two Cl atoms are on the same carbon atom. In the other, the two Cl atoms are separated on different carbon atoms. We might guess that this difference in arrangements does not matter, since in both cases, the F and Cl atoms are all bonded to the carbon atoms, and the carbon atoms are bonded together.

Our experimental observations prove this guess is wrong. There are two isomers of C 2 F 4 Cl 2 , one with a boiling point of 3 ˚C and a melting point of -57 ˚C and the other with a boiling point of 3.8 ˚C and a melting point of -94 ˚C. Differences in the arrangement of atoms in similar molecules clearly do matter, even if those differences don’t seem all that great.

In some cases, isomers have very obviously different structures. Let’s look at the various isomers with the molecular formula C 5 H 10 . Perhaps the simplest structure is one with a double bond between two of the carbon atoms. However, in a chain of five carbon atoms, there are two different places where the double bond might be. Each of these corresponds to a different compound:

The five carbon atoms don’t have to be lined up in a single chain:

One isomer of C 5 H 10 which might not have been obvious is a structure in which the five carbon atoms form a ring:

All seven of these isomers are different compounds with distinct physical and chemical properties. From these and many similar observations we can conclude as a general rule that isomers have different molecular structures, which give rise to the differing properties of the compounds.

Observation 2: molecular properties and functional groups

The previous conclusion leads us to a new question: what is it about the differences in molecular structure that produces the differences in properties? This is a huge question which, in many ways, is one of the fundamental questions of the field of Organic Chemistry. Although we cannot hope to provide all the answers to this question in this one study, we can study a few examples to develop the fundamental concept.

We begin by looking for common connections amongst molecular structures and molecular properties. From the observations we just discussed, it seems that every arrangement of the atoms in a molecule produces properties which are unlike the properties of any other molecular structure. Let’s go back and examine the two isomers of C 2 H 6 O, ethanol and dimethyl ether. As noted above, ethanol is a liquid at room temperature, and is completely soluble in water. Dimethyl ether is a gas at room temperature and is less soluble in water than ethanol.

The most notable difference between the two molecular structures is that the oxygen atom is bonded to a hydrogen atom in ethanol. There are no O-H bonds in dimethyl ether. The structure C-O-H appears in a large number of molecules. And experimentally, we find that molecules with the C-O-H group have similar molecular properties to ethanol. All are liquids at room temperature and most are soluble in water. These compounds are, as a class, called alcohols. These observations lead us to conclude that common properties are due to the common C-O-H group. The C-O-H is called the “hydroxyl group”. When we find a group of atoms which gives a specific set of properties, or “function,” to molecules, we call that group of atoms a “functional group.” Using this new term, we would say that the class of molecules called alcohols contain the hydroxyl functional group.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Concept development studies in chemistry 2012. OpenStax CNX. Aug 16, 2012 Download for free at http://legacy.cnx.org/content/col11444/1.4
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