Validity of Buffer Solution e-Module based on Problem Based Learning. Entalpi Pendidikan Kimia, [S. l.], v. 4, n. 3, p. 27–35, 2023. DOI: 10.24036/epk.v4i3.350. Disponível em: http://entalpipendidikan.ppj.unp.ac.id/index.php/epk/article/view/350. Acesso em: 26 oct. 2026.