Miscellaneous chemistry experiments
The typical non-metals have their own characteristic
chemistry, which really is very different, when compared with typical metal
chemistry. Especially the halogens and chalcogens have interesting chemical
List of fully worked out experiments:
Characteristics of an electrolysis
cell. In this experiment, the relation between voltage across and
current through an electrolysis cell is investigated. The relation
appears to be approximately exponential in the applied voltage.
High voltage electrolysis
. The experiment,
described in this page is somewhat at the border of physics and
chemistry. A salt solution is electrolysed with a plasma beam as anode,
generated from a high voltage source, supplying an output voltage of
more than 10 kV.
Nice dendritic crystal structures. A
solution of ammonium chromate is allowed to evaporate to dryness. The
solution looses ammonia, and hence ammonium dichromate is formed. Very
interesting fractal patterns are produced, with the yellow ammonium
chromate having a rather different structure than the orange ammonium
Red chemiluminiscence with chlorine
swimming pool chemicals. Hydrogen peroxide (30%) is added to some
solid swimming pool chemicals. This gives a clearly visible red
chemiluminiscence. This experiment is particularly interesting, when
done in a dark room.
Beautiful green fluorescence --
synthesis of fluorescein. Phtalic anhydride and resorcinol can be
forced to react with each other in the presence of a strong dehydrating
agent, such as concentrated sulphuric acid. The resulting compound shows
very strong and beautiful fluorescence. This is a simple, but really
Reaction between calcium and water - heat
of reaction. Calcium metal is added to water. Initially the reaction
is not that violent, but in due time, it becomes more and more violent.
Electrolysis experiments with
special effects at the cathode. Usually, the chemistry at the anode
is most interesting in electrolysis experiments, while at the cathode
just hydrogen is produced. This set of experiments demonstrates that
with suitable chemicals there also can be interesting and colorful
effects at the cathode.
Tidbits and raw material with
some nice results and ideas:
- Beautiful effects with potassium
dichromate and hydrogen peroxide. Small crystals of potassium dichromate
are sprinkled on the surface of a very dilute acidified solution of hydrogen
peroxide. The crystals remain floating on the surface, slowly releasing
dichromate in solution. This reacts with the hydrogen peroxide and this
gives beautiful effects
- Dangerous experiments with
sodium metal. Some sodium metal is put in a test tube which contains
some dilute hydrochloric acid. Hydrogen gas is produced in this reaction.
The heat of the reaction is so great, that at a certain point, the hydrogen
explodes with a loud bang.
- Violent reaction between
nitromethane and sodium hydroxide. Sodium hydroxide is added to pure
nitromethane. After a short induction period, a violent reaction occurs.
- Nice effects in petri dish
with yellow precipitate. A small amount of potassium iodide is put in a
petri dish, filled with water, and a small amount of lead nitrate is put in
the petri dish at the other side. The compounds dissolve and slowly diffuse
towards each other. When they reach each other, a yellow precipitate of
lead(II)iodide is formed. The slow diffusion results in a nice effect.
- Violence of a nitration
runaway. A nice and funny experiment. Some isopropyl alcohol is added to
a mix of nitric acid and sulphuric acid. As soon as the alcohol reaches this
mix, an exceedingly violent reaction occurs, in which a big plume of
red/brown nitrogen dioxide is formed.
- Thionyl chloride and
potassium dichromate. Potassium dichromate is dissolved in thionyl
chloride and some sulphuric acid is added. This gives some chromyl chloride
and a deep red solution. When this mix is added to water, then a violent,
but rather spectacular and in some sense beautiful reaction starts, giving a
cloud of HCl and chromyl chloride.
- Collapsing styrofoam.
Some acetone is sprinkled on a piece of styrofoam (the white packing
material, consisting of many small white bubbles). The styrofoam literally
collapses when this is done. A funny experiment which does not require any
- Making 90% nitric acid.
Standard nitric acid of approximately 60% concentration is further
concentrated to 90%, using a distillation setup and concentrated sulphuric
pure bromine. Pure and dry bromine is made from potassium bromate,
sodium bromide and sulphuric acid. A distillation setup is needed for
isolating the bromine, and concentrated sulphuric acid is used to make the
bromine perfectly dry. The potassium bromate in turn is made by
electrolysis, described in another