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:
“It so happened that, a few weeks later, Old Ernie [Ernest Hemingway] himself was using my room in New York as a hide-out from literary columnists and reporters during one of his rare stopover visits between Africa and Key West. On such all-too-rare occasions he lends an air of virility to my dainty apartment which I miss sorely after he has gone and all the furniture has been repaired.”
—Robert Benchley (18891945)
“Science is a dynamic undertaking directed to lowering the degree of the empiricism involved in solving problems; or, if you prefer, science is a process of fabricating a web of interconnected concepts and conceptual schemes arising from experiments and observations and fruitful of further experiments and observations.”
—James Conant (18931978)
“He who is conversant with the supernal powers will not worship these inferior deities of the wind, waves, tide, and sunshine. But we would not disparage the importance of such calculations as we have described. They are truths in physics because they are true in ethics.”
—Henry David Thoreau (18171862)