Scientix 9th SPWatFCL Brussels 6-8 November 2015: Robotic Platform Karel
Scientix 7th SPWatFCL Brussels 19-21 June 2015: Water through the eyes of students of different ages
Transcript of Scientix 7th SPWatFCL Brussels 19-21 June 2015: Water through the eyes of students of different ages
Pre- Primary School
Once upon a time there was a little drop. His name was…Droppie. He visited different schools in Greece, in Spain and in the Czech Republic. He wanted to tell us his story. And the story goes on like that…
Water, the chief constituent of living matter and the environment in which we live, is one of the most important chemical substances. Ordinary water, which is impure, usually contains dissolved salts and gases and sometimes organic matter.
For chemical work water is purified by distillation, and for the preparation of very pure water, distilling apparatus and vessels made of fused silica are used.
Secondary education
Pure tin vessels and pipes are often used for storing and transporting distilled water.
The physical properties of water strikingly differ from those of other substances. Water can be characterized as a clear, transparent liquid, odorless, tasteless and colorless when in thin layers but in thick layers having a bluish green color.
Very specific for water are its boiling and freezing points. 0 ° C and 100 °C are temperatures at which water freezes and boils, therefore these temperatures serve as a means of identifying water.
Water is the only naturally occurring inorganic liquid, and it is also the only chemical substance on the Earth that occurs in all three states of matter – solid, liquid, and gaseous.
The gaseous form of water is called steam. When gaseous water is mixed with other gases, as in the air, we speak of it as water vapor, when unmixed, we call it steam. Water may exist as steam a temperatures lower than 100 °C, provided the pressure is less than the usual atmospheric pressure.
If water is cooled sufficiently, it solidifies at 0 °C to ice. There is considerable expansion during the solidification, and consequently ice is lighter than an equal volume of water.
When we apply heat to ice, it melts.