Thermal Equilibrium - Change of Internal State of An Isolated System

Change of Internal State of An Isolated System

If an isolated system is left long enough, it will reach a state of thermal equilibrium, in which its temperature will be uniform throughout, but not necessarily a state of thermodynamic equilibrium, if there is some structural barrier that can prevent some possible processes in the system from reaching equilibrium. An isolated system can change its temperature or its spatial distribution of temperature by changing the state of Longley, R.G. Van Name, Longmans, Green & Co., New York, 1928, volume 1, pages 55-353, particularly pages 144-150. A system prepared as a mixture of petrol vapour and air can be ignited by a spark and produce carbon dioxide and water; if this happens in an isolated system, it will increase the temperature of the system, and during the increase, the system is not in thermal equilibrium; but eventually the system will settle to a uniform temperature. In a system prepared as a block of ice floating in a bath of hot water, and then isolated, the ice can melt; during the melting, the system is not in thermal equilibrium; but eventually its temperature will become uniform. Such changes in isolated systems are irreversible in the sense that while such a change will occur spontanteously whenever the system is prepared in the same way, the reverse change will never occur spontanteously within the isolated system; this is a large part of the content of the second law of thermodynamics. Truly isolated systems hardly occur in nature, and nearly always are artificially prepared.

Read more about this topic:  Thermal Equilibrium

Famous quotes containing the words change of, change, internal, state, isolated and/or system:

    Change of fashion is the tax levied by the industry of the poor on the vanity of the rich.
    —Sébastien-Roch Nicolas De Chamfort (1741–1794)

    Thus change the forms of being. Thus arise
    Races of living things, glorious in strength,
    And perish, as the quickening breath of God
    Fills them, or is withdrawn.
    William Cullen Bryant (1794–1878)

    The real essence, the internal qualities, and constitution of even the meanest object, is hid from our view; something there is in every drop of water, every grain of sand, which it is beyond the power of human understanding to fathom or comprehend. But it is evident ... that we are influenced by false principles to that degree as to mistrust our senses, and think we know nothing of those things which we perfectly comprehend.
    George Berkeley (1685–1753)

    The state is not “abolished,” it withers away.
    Friedrich Engels (1820–1895)

    Literature is not exhaustible, for the sufficient and simple reason that a single book is not. A book is not an isolated entity: it is a narration, an axis of innumerable narrations. One literature differs from another, either before or after it, not so much because of the text as for the manner in which it is read.
    Jorge Luis Borges (1899–1986)

    The twentieth-century artist who uses symbols is alienated because the system of symbols is a private one. After you have dealt with the symbols you are still private, you are still lonely, because you are not sure anyone will understand it except yourself. The ransom of privacy is that you are alone.
    Louise Bourgeois (b. 1911)