In the orthogonal system of coordinates each couple of coordinate axes sets the plane which divides space into two equal half. In three-dimensional space of such mutually perpendicular planes three, and all coordinate space is divided by them into eight equal areas. These areas are called "octants" - on designation of the eight in Latin.

Sucrose formula – C12H22O11, ethyl acetate – C4H8O2. Having written a structural formula of CH3-CH2-O-CO-CH3 ethyl acetate, you will see characteristic of the structure of this substance – two organic molecules containing 2 atoms of carbon kind of "connected" via oxygen "bridge". And one of these molecules differs from ethyl alcohol only in lack of the only atom of hydrogen. Therefore the general chain of transformations is clear: at first to receive ethanol from sucrose, and then to turn it into ethyl acetate.

The atmosphere of Earth is called sometimes the fifth ocean. And just as the oceans consisting of water it is in the continuous movement. This movement is also called wind.

It is much more interesting to study the principle of operation of the nuclear reactor at school if there is its animated model. His school students can make even in the summer, during the out-of-school classes. And when academic year will begin, they learn purpose of each of nodes of the reactor.