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题目内容
题目材料：
A significant proportion of meteorites contain chondrules, small, glassy silicate spheres. The importance of chondrules is that they show that at some time the temperature was so high that the chondrule material was vaporized. The vapor then cooled quickly and the liquid silicates, condensing out of the vapor, formed small silicate spheres under the influence of surface tension. When these spheres solidified, they were incorporated into silicate fragments, and the material was eventually compressed into rock by gravitational forces. The fact that the chondrules cooled very quickly is revealed by the composition of the minerals within them. In the vapor phase, whole minerals would not have existed, but there would have been components that, combined in various ways, can form different minerals. Combinations of these components produced an initial collection of minerals within chondrules when they formed and, while the silicate was hot, the components changed partners to form more stable minerals一meaning ones of lower energy. Given enough time, the minerals in chondrules would have had the lowest possible energy consistent with using all available components; the mixture of minerals would then be equilibrated. However, the mixtures of minerals in chondrules are nonequilibrated-corresponding to a total energy far greater than the minimum possible. This shows that the chondrules became solid and cooled so quickly that the nonequilibrated state became frozen in, since individual components did not have enough energy to jostle their way through the material to form more stable minerals.
以上解析由 考满分老师提供。
