Which chemical symbols will complete the equation for this decomposition reaction? 2KI → 2_ + _ 2

The tilt of the earth's axis of rotation is responsible for the a) ocean's tides. b) size of the moon. c) brightness of stars. d) earth’s seasons.

How many protons, electrons, and neutrons are in each of the following isotopes? a. zirconium-90 b. palladium-108 c. bromine-81 d. antimony-123

How can the periodic table be used to predict the behavior of elements?