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what can be said about a reaction with h = 620 kj/mol and s = -0.46 kj/(molk)?

a. it is spontaneous above 1347 k.
b. it is always spontaneous.
c. it is spontaneous at 298 k.
d. it is never spontaneous.

How have the greenhouse gasses increased from the year 2000 to 2018

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.

If a simple machine aduces the strength of a force, what must be increased? the speed of the input force the work the simple machine performs the size of the simple machine the distance over which the force is applied