One of the chemical compounds that are crucial for the existence of all life on Earth is water. As other materials, it can be in different states of aggregation.
One of them - the water vapor.
Water vapor is the gaseousstate of aggregation of water. It is formed by its individual molecules in the process of evaporation. Water vapor under normal physical conditions is completely transparent, no odor, taste and color. However, in the condensation of saturated water vapor, mixed with other gases, may form tiny droplets. They effectively scatter light. Therefore, the water vapor can be seen in this state.
On Earth, the water vapor contained in the atmosphere. They play a crucial role in the course of various natural processes, as well as a direct impact on the life of plants, animals and people. The content of water vapor in the air is called humidity. There are absolute and relative humidity. For humidity indicator used hygrometers or psychrometers devices.
The most important place today takes in water vaporIndustry and many branches of engineering. It is used as the working fluid in the conversion of heat energy into kinetic energy and electricity with the help of various types of steam engines - steam power plants, steam turbines. Due to the relatively high heat capacity and the possibility of being heated to a temperature above 100 ° C, steam is widely used as a coolant. For example, in steam heating systems.
A study of steam began in the XVI century. The first scientific work dedicated to its properties, was published in the XVII century, John. Port. With the wide spread of steam engines in the XIX-XX centuries steam again attracted the attention of scientists. So, in the middle of the XX century we made a serious study of the behavior of steam at high pressures. The research results were presented at the Fourth International Conference on the properties of water vapor, which was held in New York in 1963.</ P>