Thermodynamics Paper Essay Example | Topics and Well Written Essays - 500 words

Thermodynamics Paper - Essay Example With most substances, the temperature and pressure related to the triple point lie below standard temperature and pressure and the pressure for the critical point lies above standard pressure.   Generally, at normal pressure, as temperature rises, most substances convert from their solid state, to liquid and lastly to a gaseous state. In the same reverse sequence, at standard temperature as pressure decreases, most substances change from the gaseous state to liquid and eventually to the solid state. As noted earlier there are three states of matter, these state are commonly referred to as the phases and they are gas, liquid, and water. In addition to this it is well evidenced that most substances can exist in different states under different conditions, mainly the surrounding temperature and pressure. In the case of water it exists as a solid i.e. ice at temperatures below 0o  C, and as a gas at temperatures above 100o  C. It is important to understand that in most cases the evaluation of these different states is commonly carried out in the near earth environment. This is important to be noted because any given environment is mainly characterized by the temperature and pressure (Gupta 180). Hence under these two parameters, water is in its liquid state at normal atmospheric pressure and at a temperature of 99o  C, however, when the pressure is at 71 cm and the temperature remain constant at 99o  C the phase is changed to a gas. In most substances their boiling points are lowered as the pressure decreases, moreover, their melting point reduces as the pressure decreases. However, the melting point of water is an exception to this rule; ‘It gets lower as the pressure gets higher’ (Gupta 79) Real gases react in the same way just like ideal gases at high temperatures. However, under low temperatures the connections between the molecules and their volume