Vaporization (evaporation) is the process whereby atoms or molecules in a liquid state (or solid state if the substance sublimes) gain sufficient energy to enter the gaseous state. See also: Vaporizer.
The thermal motion of a molecule must be sufficient to overcome the surface tension of the liquid in order for it to evaporate, that is, its kinetic energy must exceed the work function of cohesion at the surface. Evaporation therefore proceeds more quickly at higher temperature and in liquids with lower surface tension. Since only a small proportion of the molecules are located near the surface and are moving in the proper direction to escape at any given instant, the rate of evaporation is limited. Also, as the faster-moving molecules escape, the remaining molecules have lower average kinetic energy, and the temperature of the liquid thus decreases.
If the evaporation takes place in a closed vessel, the escaping molecules accumulate as a vapour above the liquid. Many of the molecules return to the liquid, with returning molecules becoming more frequent as the density and pressure of the vapour increases. When the process of escape and return reaches an equilibrium, the vapour is said to be saturated, and no further change in either vapour pressure and density or liquid temperature will occur.
Gas has less order than liquid or solid matter, and thus the entropy of the system is increased, which always requires energy input. This means that the entropy change for evaporation (ΔHevaporation) is always positive.
Forced evaporation is a process used in the separation of mixtures, in which a mixture is heated to drive off the more volatile component (e.g. water), leaving behind the dry, less volatile, component.
It is a misconception that at 1 atm, water vapour only exists at 100°C. Water molecules are in a constant state of evaporation and condensation flux near the surface of liquid water. If a surface molecule receives enough energy, it will leave the liquid and turn into vapour pending an allowable vapor pressure. Under a pressure of 1 atm, water will boil at 100°C.
Factors influencing rate of evaporation
The fuel droplets vapourise as they receive heat by mixing with the hot gases in the combustion chamber. Heat(energy) can also be received by radiation from any hot refractory wall of the combustion chamber.
|Time to end: 22h 51m 58s|
|Solid clear thick glass pipe. Inside-out blown,...|
Now for even better prices!
Are you looking for an advantageous economical purchase of more glass pipes and bongs? Check out our discounted pipe sets. We have combinations of water bongs, pipes, and chillums or one hitters for every occasion.
Our water bongs, glass pipes, bubblers, one hitters etc. are hand-made exclusively in small workshops. These workshops provide sophisticated, high-quality craftsmanship of each piece. Our glass water bongs, glass bubblers, and glass pipes are truly small works of art, and you can buy these glass pipes and water bongs in online smoke shop for close to production cost! Only premium materials, such as raw silver, 24ct gold, borosilicate glass (Pyrex, Simax), and American grade non-toxic colors are used for our products. We have been making glass smoking devices for over ten years and have thousands of satisfied customers.
Our glass products are also well known for their great color-changing effects (CCG pipes). This is achieved by adding raw silver on the glass surface under high temperatures. The COOL look of the bongs, pipes, and one hitters comes with color changes, as they eventually get dirty from the inside. Our merchandise photos depict the look of the product in normal daylight. Unlike many of our competitors, we are not trying to fool our customers.
Most of these glass beauties are made by us, so we can create and modify your products specifically for you. You can place your own inscription (initials, name, slogan, sign) on any of our customized water bongs or glass pipes!
E-shopping in our smoke shop is easy, comfortable, safe, and discreet. Hundreds of customers shop with us every day, and the majority of our glass pipes and bongs are being sent mainly to the USA.
Water pipes or water bongs are devices commonly used for smoking, usually tobacco or other herbal substances. Smoke is bubbled through a chamber containing water. The bong enables you to smoke in a manner which is very different from a simple smoking pipe.
Also, blown glass pipes differ from clay or wooden pipes. The main difference is that glass pipes consist of just one piece of material. They are designed to be portable and can be used for a shorter smoke. Pipes made of pyrex or other types of heat resistant glass protect your hands.
Water bongs provided in our smoke shop were tested during MarijuanaRadio show on 2008 and even Tommy Chong likes our stuff.
The smoke shop was founded in 2001 and has plenty of satisfied customers.:) We also have good references reviews from the website - Weeds That Please. Try our high quality products yourself, buy water bongs and glass pipes in our online smoke shop!