MYTUTOR SUBJECT ANSWERS

605 views

What is chirality/optical isomerism?

Chirality (or optical isomerism) is a physical property of a molecule which has a non-superimposable mirror image. In other words, a molecule which, when reflected cannot be rotated in any way to make the original molecule. 

The simplest example of this is human hands, they are mirror images but cannot be superimposed upon one another. Another example is the letter R. You can prove this to yourself by looking at your hands side by side with both palms facing towards you and try to superimpose them. You'll soon see that no matter how much you rotate them, they will not fit on top of one another.

The most common optical isomers are 'asymmetric' carbons, those with 4 different groups bonded to them (e.g. (NH2)HC(OH)(COOH) ), however it can be found in coordination complexes and even larger organic molecules. Optical isomers are indistinguishable in their chemical properties as they take part in the same reactions with achiral reagents, however if polarised light is passed through a solution of a chiral molecule, it will be rotated slightly. Passing polarised light through this molecule's optical isomer will rotate the light the same amount in the opposite direction.

Another key difference of two optical isomers is how they interact with biological systems, most notably enzymes (which are themselves chiral). Often, only one optical isomer will take part in reactions catalysed by enzymes and the other will not react at all (due to the importance of shape in enzyme active sites). A perfect example of this is the molecule carvone, one isomer of which smells like spearmint and the other of caraway seeds. The difference in smell is due to the different interaction with receptors in the nose. 

Matthew W. GCSE Chemistry tutor, A Level Chemistry tutor, GCSE Maths ...

2 years ago

Answered by Matthew, an A Level Chemistry tutor with MyTutor


Still stuck? Get one-to-one help from a personally interviewed subject specialist

98 SUBJECT SPECIALISTS

£24 /hr

Eilidh F.

Degree: Natural Sciences (Bachelors) - York University

Subjects offered:Chemistry, Maths+ 2 more

Chemistry
Maths
Further Mathematics
Biology

“About me: My name is Eilidh (pronounced Aylee) and I am a student at the University of York. I study Natural Sciences specialising in Neuroscience, and have always loved both Science and Maths. I also reallyenjoy teaching, meeting new...”

£22 /hr

Laura L.

Degree: Chemistry (MCHEM) (Masters) - Warwick University

Subjects offered:Chemistry, Maths+ 1 more

Chemistry
Maths
Biology

“Hi there! I'm a third-year Chemistry student, I tutor maths from 11+ to A level as well as GCSE Science, A level Biology, and Chemistry”

£24 /hr

Julia M.

Degree: Sustainable Agriculture and Food Security (Masters) - Edinburgh University

Subjects offered:Chemistry, Maths+ 1 more

Chemistry
Maths
Biology

“Enthusiastic friendly tutor looking for curious and ambitious students for fun and relaxed lessons”

About the author

£30 /hr

Matthew W.

Degree: Chemistry (Masters) - Durham University

Subjects offered:Chemistry, -Personal Statements-

Chemistry
-Personal Statements-

“Chemistry undergraduate at Durham University keen to help you with your studies!”

You may also like...

Other A Level Chemistry questions

How would you synthesise an carboxylic acid just from a primary haloalkane like bromoethane?

Why is scandium not considered a true transition metal?

NaOH is a strong base. An aqueous solution is made containing 0.300mol.dm^-3 of NaOH at room temperature. Calculate the pH of this solution.

What is the difference between covalent and dative covalent bonds?

View A Level Chemistry tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok