B, using the metaphors of "ice jam in Sichuan" and "snow all over the mountain", it shows that a person's career path is blocked, the ideal of saving the country and the people cannot be realized, and there is no chemical change, so B is wrong;
A mist from Yungu and Menggu has enveloped Yueyang City. It means that the clouds on the lake roll and transpiration, diffuse and cover the whole cloud dream; Boundless waves, surging, the majestic Yueyang city also shook, what momentum and strength is this, there is no chemical change, so C is wrong;
D, this poem contains three chemical reactions:
(1) "Not afraid of being crushed into pieces" means that calcium carbonate is decomposed into calcium oxide CaCO3 at high temperature? CaO+CO2↑;
② Calcium oxide reacts with water to produce hydrated lime Cao+H2O = Ca (OH) 2;
(3) Then stick it on people's walls, that is to say, "keep the world clean" Ca (OH) 2+CO2/CaCO3+H2O. This is a long process, so D is correct.
So choose D.