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some reactions that are considered to be spontaneous at low temperatures will not proceed at a measurable rate or form any measurable quantity of products for several hours, days, or years.

a. explain why this is.
b. will the addition of a catalyst alter the value of delta "G" for the reaction? explain.

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i'm not sure for an answer for A, but i think b will be a yes because a catalyst lowers activation energy and will take less time for a reaction to occur. help plz?

thanks!

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  1. (a) A high activation energy may slow down a spontaneous reaction to the point that it does not occur at a visible rate.
    (b) A reaction is spontaneous because it leads to lower potential energy (deltaH is negative) and/or it increases entropy (deltaS is positive). DeltaH and deltaS are independent of the activation energy which catalysts can change.
    DeltaG is defined in terms of deltaH and deltaS neither of which depends on the activation energy or on catalysts.

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