The students that are joining the Chemistry course are students from the first semester of college and come from high school with very heterogeneous knowledge and skills. Usually, their proficiency in the science area's disciplinary skills is very low, being the fact that they possess limited abstraction capacities a central problem because this prevents them from visualizing molecules, phenomena, and microstructures correctly. According to data obtained by the Institutional Effectiveness Department, the average failure rate for this class is near 20%. This project develops five activities where virtual reality and augmented reality technologies are used as an innovative didactic strategy in the Chemistry course. These activities were applied to pilot and control groups where the results show at a 95% level of confidence that the grades' medians in groups where these technologies were used during class are higher than those in groups with traditional teaching. Thus, virtual reality and augmented reality experiences, based on content and disciplinary and transversal skills from the Chemistry course managed to help the students get a higher proficiency level in these.

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In this study, we demonstrated the effects of chemical treatments for Halloysite nanotubes (HNTs) under acid and alkaline conditions using sulfuric acid and sodium hydroxide. XRD results indicate that alkaline treatment destroyed the crystalline structure and morphology for HNTs because the XRD spectrum shows the typical peaks for montmorillonite. For the acid treatment using H 2 SO 4 , XRD spectrum indicates an intensity reduction for the peak (001) showing a lower concentration of aluminium in the structure. Diffuse reflectance analysis shows a reduction of 40 and 15% for reflectance with H 2 SO 4 and NaOH treatments respectively. A terephthalic acid adsorption test was realized with the HNTs, modified halloysites (HNT-H 2 SO 4) and (HNT-NaOH) samples with a kinetic study and it was quantified with UV spectroscopy at 240 nm where results shown a lower adsorption for HNTs treated with H 2 SO 4 in comparison with alkaline treatment and not treated HNT. A decrease of 58% ± 0.3was achieved with the sulfuric acid treatment with not crystalline structure modification using ICP technique to quantify the sample compositions.

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