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THÍ NGHIỆM 10
+
1.Phản ứng giữa carbon và oxy
C + O2 CO2
O2
C
O2
C
CO2
phân tử cacbon chưa phản ứng
CO2
2.Phản ứng giữa Natri và oxy
4Na + O2 2Na2O
+
Na
O2
to
+
Na
O2
phân tử Natri chưa phản ứng
phân tử Natrioxit
phân tử Natrioxit
Thí nghiệm 10
Phản ứng giữa đồng(II) oxit và hyđro
CuO
H2
CuO
H2
+
+
to
to
H2
CuO
H2O
+
Cu
4.Phản ứng giữa hydro và oxy
2H2 + O2 2H2O
+
2H2
O2
to
+
2H2
O2
to
2H2O
5.Phản ứng giữa sắt và axit clohydric
Fe + 2HCl FeCl2 + H2
Fe
2HCl
+
Fe
2HCl
+
Chirality
Take the molecule on the left and make its mirror image.

OH
H
CH
3
H
*
*

H
HO
CH
3
H
*
*
Chirality
Flipping the reflection does not give a super-imposable compound!

OH
H
CH
3
H
*
*

CH
3
H
H
OH
*
*
Chirality
Flipping the reflection does not give a super-imposable compound!

The methyl groups
do not line up.

CH
3
H
H
OH
*
*
Chirality
These are examples of yet another type of isomer!
They are optically active (ie chiral).
But they are not mirror images.
They are called diasteriomers.
Chirality
The situation is actually a little more complex as there is another chiral carbon in the molecule.
Can you find it?
For ‘n’ chiral carbons in a molecule there are up to ‘2n’ optical isomers.
Chirality

CH
3
H
H
OH
*
*

CH
3
H
H
OH
*
*
Chirality - Racemates
What happens when HBr is added to the alkene 1-butene?
An addition reaction occurs.
The product is 2-bromobutane.
(The Markovnikov product)
Is the product optically active?
Chirality - Racemates
The result is an addition which gives a chiral carbon.
Chirality - Racemates
The result is an addition which gives a chiral carbon.
Chirality - Racemates
But in fact the addition can occur from either side!



Both compounds
are optically active,
but the mixture is not.
Chirality - Racemates
A mixture that contains both enantiomers is called racemic.
Most chemical reactions produce racemic mixtures.
Most biochemical reactions produce only one optical isomer and are not racemic.
Chirality - Review
Compounds can be chiral if there is a carbon which has four different groups.
Chiral compounds are said to be optically active as they can rotate the plane of polarised light.
Enantiomers are non super-imposable mirror images.
Chirality - Review
Diasteriomers are optically active compounds which are not mirror images of each other.
Diasteriomers must have at least two chiral carbons.