Key Concepts For Doing Enthalpy Calculations
- When a reaction is reversed, the magnitude of ΔH stays the same, but the sign changes.
- When the balanced equation for a reaction is multiplied by an integer, the corresponding value of ΔH must be multiplied by that integer as well.
- The change in enthalpy for a reaction can be calculated from the enthalpies of formation of the reactants and the products
- Elements in their standard states are not included in the enthalpy calculations for the reaction since the enthalpy of an element in its standard state is zero.
Read more about this topic: Standard Enthalpy Of Formation
Famous quotes containing the words key, concepts and/or calculations:
“The hypothesis I wish to advance is that ... the language of morality is in ... grave disorder.... What we possess, if this is true, are the fragments of a conceptual scheme, parts of which now lack those contexts from which their significance derived. We possess indeed simulacra of morality, we continue to use many of the key expressions. But we havevery largely if not entirelylost our comprehension, both theoretical and practical, of morality.”
—Alasdair Chalmers MacIntyre (b. 1929)
“During our twenties...we act toward the new adulthood the way sociologists tell us new waves of immigrants acted on becoming Americans: we adopt the host cultures values in an exaggerated and rigid fashion until we can rethink them and make them our own. Our idea of what adults are and what were supposed to be is composed of outdated childhood concepts brought forward.”
—Roger Gould (20th century)
“What, really, is wanted from a neighborhood? Convenience, certainly, an absence of major aggravation, to be sure. But perhaps most of all, ideally, what is wanted is a comfortable background, a breathing space of intermission between the intensities of private life and the calculations of public life.”
—Joseph Epstein (b. 1937)