The purpose of this randomized experimental study is to apply two socio-cognitive models to understand possible ways to improve students' learning outcomes in an online introductory chemistry learning environment. Specifically, the social presence theory suggested that students' sense of relatedness and learning motivation can be increased by a real or imagined interaction with others. On the other hand, self-regulated learning theory and self-determination theory both suggested that students learn best when they direct their focus to self, rather than others. Using these two theoretical perspectives as the basis, two experimental conditions (social presence vs. self-regulated) were developed in the context of chemistry learning. Participants of the study were randomly assigned to one of the experimental conditions. Both groups were presented with a pre-test, an online micro-lecture on balancing equations, i.e., a subtopic of stoichiometry, and a post-test. Linear mixed model analysis revealed that participants in the self-regulated learning condition had higher improvement in quiz scores than had participants in the social presence condition. Implications of the study and future directions were discussed.