Chemical reactions
&
Solutions
Water



Water is a polar molecule
Charge is not uniformly distributed.
Excess negative charge is found on the oxygen
due to its ability to attract electrons.
The attraction that results between neutral atoms with a
negative charge excess at H is called hydrogen bonding.
This attraction gives water
many of its properties.
March 23, 2016
GSCI 163 Spring 2010
Polar
Like dissolves like
For polar solutions the attraction of
one water molecule for another will
squeeze out material that separates
the water molecules unless these
molecules carry charge. The charge
of the intermediate material
maintains the attraction and so the
material remains.

March 23, 2016
GSCI 163 Spring 2010
Sugar ?
sucrose, lactose, and fructose
 Sucrose  table sugar

• C12H22O11
Note the hydroxide ions OH-
C
C
C
C
March 23, 2016
C
C
C
C
There are several sites on the
molecule that tend to have a
negative charge. Sugar is
therefore a polar molecule
C
GSCI 163 Spring 2010
C12H22O11




12x12+22x1+16x11=319.99 gm/mole
At 0°C, 179 grams of sucrose will dissolve
at 100°C. 487 grams will dissolve.
211.5
g/100 ML @ 25oC
March 23, 2016
GSCI 163 Spring 2010
Redox



Oxidation Reduction
Oxidation is the loss of electrons or an increase
in oxidation state by a molecule, atom or ion.
Reduction is the gain of electrons or a decrease
in oxidation state by a molecule, atom or ion.
March 23, 2016
GSCI 163 Spring 2010
Two formula approach
H2 + F2 -> 2HF
[H->H++e-]
Fe + CuSO4 → FeSO4 + Cu
March 23, 2016
[F +e- ->F-]
[Fe->Fe+2 + 2e- ]
GSCI 163 Spring 2010
[Cu+2 +2 e- ->Cu]