Calories to heat 15 g of water from 19 ∘C to 23 ∘C.

the ratio of the conjugate base to the acid required to attain the desired ph.

i belive it is water

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.