To watch a shortened version of the video records, pull the mouse on the first pictures of them displayed below. The positioning of the records is reverted with 180 degrees.
The concentration of the outer electrolyte is 8 M/l, and that of the inner electrolyte is 0.732 M/l.

Shrinking of a Reaction Zone
	Beside a shrinking reaction zone bordered by two regressing edges (in the middle) several travelling reaction zones can be observed. The angle of the oblique lines which border the region filled with precipitate by the decreasing reaction zone from the empty (precipitate-free) part of the gel are determined by tho perpendicular velocities: the speed of the diffusion front, and that of the reaction zone's regressing edges. The travelling reaction zones are bordered on one side by a blind band and on the other side by a regressing edge. The reaction presented on the video record was taking place in 20' in real time.
	Millimeter Scale

Shrinking of a Reaction Zone

     Beside a shrinking reaction zone bordered by two regressing edges (in the middle) several travelling reaction zones can be observed.
     The angle of the oblique lines which border the region filled with precipitate by the decreasing reaction zone from the empty (precipitate-free) part of the gel are determined by tho perpendicular velocities: the speed of the diffusion front, and that of the reaction zone's regressing edges.
     The travelling reaction zones are bordered on one side by a blind band and on the other side by a regressing edge.
     The reaction presented on the video record was taking place in 20' in real time.

Millimeter Scale

Birth of a Reaction Zone
	A reaction zone has been splitted and beside an empty region two new reaction zones have been formed. The video record presents the process when, beside the progressig of the reaction zones born by "pair-production" new precipitate emerges in the empty region as well. A thin band between the former and the newly formed precipitate remain empty all the time. These blind bands are the dark oblique lines shown on the movies. The reaction presented on the video record was taking place in 12'20'' in real time.
	Millimeter Scale

Birth of a Reaction Zone

     A reaction zone has been splitted and beside an empty region two new reaction zones have been formed. The video record presents the process when, beside the progressig of the reaction zones born by "pair-production" new precipitate emerges in the empty region as well.
     A thin band between the former and the newly formed precipitate remain empty all the time. These blind bands are the dark oblique lines shown on the movies.
     The reaction presented on the video record was taking place in 12'20'' in real time.

Millimeter Scale

Advancing Reaction Zones - Close-Up
	Close-up of the progressing of reaction zones which are bordered on one side by a regressing edge, and on the other side by a blind region. Note that the zones are not any more paralell with the diffusion front. According to the results of the X-ray scattering experiments the brown precipitate is CuO. The structure of the blue matter is not yet clarified, but probably it is Cu(OH)₂. The reaction presented on the video record was taking place in 12'35'' in real time.
	Millimeter Scale

Advancing Reaction Zones - Close-Up

     Close-up of the progressing of reaction zones which are bordered on one side by a regressing edge, and on the other side by a blind region. Note that the zones are not any more paralell with the diffusion front.
     According to the results of the X-ray scattering experiments the brown precipitate is CuO. The structure of the blue matter is not yet clarified, but probably it is Cu(OH)₂.
     The reaction presented on the video record was taking place in 12'35'' in real time.

Millimeter Scale

Advancing Reaction Zones
	Advancing of reaction zones seen from below. The reaction presented on the video record was taking place in 12'50'' in real time.
	Millimeter Scale

Annihilation of Reaction Zones
	The annihillation of two approaching reaction zones can be observed. While this event is taking place, a small cusp is forming at the meeting point of the reaction zones. The reaction presented on the video record was taking place in 12'10'' in real time.
	Millimeter Scale

Birth of a Small Spiral
	An interesting, seldom phenomenon can be seen on the record: the formation of a spiral in a gel sheet. Spiral-shaped reaction zones are usually forming under certain circumstances in the experiments performed in the test-tubes, where they can move in a two-dimensional area, and they can perform complicated motions. In this experiment the small spiral is formed in a 1.6 mm thick gel sheet. The reaction presented on the video record was taking place in 13'50'' in real time.
	Millimeter Scale

Birth of a Small Spiral

     An interesting, seldom phenomenon can be seen on the record: the formation of a spiral in a gel sheet. Spiral-shaped reaction zones are usually forming under certain circumstances in the experiments performed in the test-tubes, where they can move in a two-dimensional area, and they can perform complicated motions.
     In this experiment the small spiral is formed in a 1.6 mm thick gel sheet.
     The reaction presented on the video record was taking place in 13'50'' in real time.

Millimeter Scale

[Homepage of Peter Hantz] [Additional experimental data to "Pattern Formation in the NaOH+CuCl₂ Reaction"]

This page is maintained by P. Hantz . Last modified 11.06.2002.