Which of the following describes a perpetual-motion machine? A. A battery that contains one oxidized metal and one reduced metal
B. A renewable energy source
C. A motor that requires no energy input once it is running
D. An electric motor that is powered by an electromagnet
SUBMIT

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