Colored gases - chlorine and chlorine dioxide . Two experiments are performed. In one of them, chlorine gas is made from dilute hydrochloric acid and calcium hypochlorite. In the other, chlorine dioxide is made from sodium chlorate and concentrated hydrochloric acid. The chlorine dioxide has a really intense yellow color.

Volatile compounds of chromium - another colored gas . In this experiment, two volatile compounds of chromium are made from potassium dichromate, sodium fluoride, sodium chloride and concentrated sulphuric acid. One of them produces an orange/brown vapor, which very much resembles bromine vapor.

More fun with volatile chromium - chromyl chloride . This is a really beautiful experiment. Chromyl chloride vapor is poured on a very dilute acidified solution of hydrogen peroxide. On the surface, the chromyl chloride vapor is absorbed by the liquid and heavy streams of a peroxo complex of chromium are formed, which produce nice deep blue patterns in the liquid.

Violent 'combustion' of acetylene in chlorine gas . Acetylene gas, made from reacting water with calcium carbide (a.k.a. 'carbid) is bubbled into an erlenmeyer, filled with chlorine gas. This results in violent explosions inside the erlenmeyer. Spectacular, but also somewhat scary.

Decomposition of iodoform, purple iodine vapor. A small amount of iodoform is heated in a test tube, and it is shown how this decomposes, giving purple vapor of iodine.

Reaction between molten nitrite and iodate, beautiful red gas mix. Some potassium hydrogen diiodate (double salt of potassium iodate and iodic acid) is mixed with sodium nitrite and the mix is heated. This gives a mix of nitrogen dioxide and iodine vapor. This mix has a beautiful color.

Volatile compound of niobium - rime and snow. This is an experiment at the border of chemistry and physics. Some niobium pentachloride is heated, until all of it has become a vapor. The vapor has a deep yellow color. On cooling down, the vapor condenses to a very fine snow-like material. Inside the test tube, one can see the 'snow' falling. Also, rime is formed. This is a beautiful somewhat mysterious experiment.

Volatile compound of tin with yellow vapor color. Tin and iodine are made to react in a suitable solvent for iodine. Under these conditions the interesting compound tin(IV) iodide is formed, which can easily be isolated. This compound is volatile and only moderate heating is needed to give a dense yellow/brown vapor.

Volatile vanadium compound, leading to green gas and red smoke. Phosphorus pentachloride is capable of chlorinating vanadium pentoxide and the resulting compound is volatile and gives rise to formation of interesting yellow/green vapor and red smoke when it is heated.

Reaction in gas phase. Nitrogen monoxide and oxygen are prepared and mixed by setting up an apparatus with two glass bottles. As soon as the gases mix, a deep brown gas is formed.

Electrolysis of water -- detonating gas. Water is decomposed by means of electrolysis of a dilute sulphuric acid solution. The resulting gases are mixed and the impressive explosive power of this gas mix is demonstrated.

Precision electrolysis of acetate and formiate. Acetate and formiate are electrolysed and based on the observations in this experiment, the net reactions are derived. A demonstration of what can be achieved with a combination of careful observation and reasoning.

Color of the flame of burning gases. Different gases are collected in a test tube, sucked in a syringe, and then ignited. Many different flame colors can be obtained from different gases. Some flame colors are remarkable, such as pink/rose and grey.

Explosive properties of chlorine dioxide . The brightly colored chlorine dioxide gas is prepared and ignited. This results in a nice and quite spectacular decompositon reaction.

Explosion of chlorine dioxide, initiated by presence of ammonia . Another experiment, which demonstrates the danger of chlorine dioxide. This experiment shows how chlorine dioxide can be brought to explosion, simply by adding a few drops of household ammonia.

Barking dog reaction . Nitrous oxide is mixed with carbon disulfide vapor and this mix is ignited. This results in a very spectacular reaction with bright light and an impressive barking noise.

Self-ignition of phosphine in chlorine gas . In this experiment some phosphine is prepared, and the gas is bubbled in an atmosphere of chlorine, resulting in self-ignition of the gas and contraction of gas volume.

Formation of a self-igniting gas from fine sand powder and magnesium . Magnesium metal and finely powdered sand are reacted to form magnesium silicide, which in contact with dilute acids produces self-igniting silane gas. This is a spectacular, but somewhat dangerous experiment.

Concentrating and purification of ammonia. Ordinary household ammonia is concentrated and purified by heating the liquid, driving out the gas and leading that gas through distilled water. This process can be used to make very pure ammonia at a higher concentration than the plain household ammonia.