Which of the following is an alkaline earth metal? A. Silicon (Si)
B. Aluminum (Al)
C. Carbon (C)
D. Magnesium (Mg)

The following transition occurs at a molecular level for a substance. what transition corresponds to this change in microscopic structure? the carbon dioxide molecules on the left are in a regular, tightly packed pattern. after heating, it becomes much lower density. a. melting b. boiling c. sublimation d. freezing