Is lattice energy usually endothermic or exothermic?

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?

Determine the empirical formula for succinic acid that is composed of 40.60% carbon, 5.18% hydrogen, and 54.22% oxygen.

Identify the lewis acid in this balanced equation: ag+ + 2nh3 -> ag(nh3)2+a. ag+b. nh3c. ag(nh3)2+