The periodic table allows students to easily understand the chemical elements and predict the behavior of theoretical yet undiscovered new elements. Many memorization techniques have been used for learning the periodic table, yet serious games (i.e., designed for a primary purpose other than pure entertainment) have been underexplored to complement or even replace such memorization techniques. Since CHEMMEND, an existing physical card game, was found to assist with learning the periodic table, we explore the potential of E-CHEMMEND, a digital version of the game as an aid to memorize the group and period numbers of the elements. E-CHEMMEND is a single-player serious game to explore the effect of four different game conditions involving two experimental factors that account for different educational scenarios. The first factor investigates the role of playing through levels of increasing difficulty versus playing with all elements from the very beginning. The second factor investigates the role of displaying the group and period numbers of the chemical element along with its symbol versus only displaying the element symbol. Preliminary results show that E-CHEMMEND is perceived as more enjoyable when the group and period numbers are displayed. In contrast, the game is found to better assist learning when this information is hidden and levels are shown. Taken together, our results suggest that a variety of educational purposes can be accommodated with a range of game settings. Ultimately, the design rationale and the lessons learned while testing E-CHEMMEND will be valuable for chemistry instructors and education researchers. A desktop-based Windows executable version of the game is available at http://www.chemmend.uji.es/game.