The purpose of this article was to evaluate the effectiveness of using mobile augmented reality (AR) instructional material for Year 10 science students in a secondary school in Brunei Darussalam. Specific learning styles were identified for the control and the experimental groups. A mobile AR application of instructional material was developed for year 10 chemistry lesson focusing on redox reaction using Vuforia SDK and Unity3d. The material developed consisted of visual, audio and kinesthetic elements of learning modalities which aimed to stimulate students' interest and improve their learning ability. The t-test (t = -3.39) in the posttest indicate d a significant result (p = 0.00152) between the mean scores of the experimental (mean = 42.72) and control (mean = 26.36) groups. The result showed that the intervention of classroom lessons introduced by the mobile AR application had a significant positive impact on the learning outcome and supported the idea that AR can be a valuable teaching tool. Qualitative analysis also indicated that it improved the liveliness of the learning environment and the interaction amongst the students.