Search the grid for the 5 tiles underneath and note their coordinates: like Battleship. Fair warning: they may have been rotated! But that’s not the only transformation you need to be prepared to do in this experiment.
The letter pairs yielded by the coordinates in the grid also need to be transformed using the key to the right of the grid; each resulting letter pair represents an element found on the periodic table.
Here’s the periodic table of the elements for those of you who don’t already have it memorized.
Almost there! Use the arrows to find an adjacent element, and then perform the same transformation on that element. Now you have an appropriate answer word for what you see pictured here, plus one extra letter to use in your process of elimination. Nobody said chemistry was going to be easy.