Which of the following statements is true? a. ΔHfus = ΔHsolid
b. ΔHfus = –ΔHsolid
c. Hfus is always negative.
d. ΔHsolid is always positive.

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

Describe the interaction that occurs between two objects with the same electrical charge.

How many moles of cu are needed to react with 5.8 moles of agno3? cu + 2 agno3 → cu(no3)2 + 2 ag