【简答题】1-11. 乙醚和正丁醇具有相似的水溶性,但二者沸点相差极大,为什么? Diethyl ether and 1-butanol are isomers, and they have similar solubilities in water. Their boiling points are very different, however. Explain why these two compou...
【单选题】【图片】Ionic solids tend to be very stable compounds. The enthalpies of formation of the ionic molecules cannot alone account for this stability. These compounds have an additional stability due to th...
A.
The dissociation of a compound is always an endothermic process .
B.
the heat of formation of a compound may be positive or negative
C.
The overall change in energy of a process can be determined by breaking the process down into steps , then adding the changes in energy of each step .
D.
Sublimation energy, the energy required to cause a change of phase from solid to gas, by passing the liquid phase. has always a positive value