SRIVASTAVA, Amar. The Effectiveness of Hands-on Activity Teaching in Learning Acid and Base Concepts at the Secondary Level. SCHOOL SCIENCE, [S. l.], v. 55, n. 2-3, p. p.17–20, 2017. Disponível em: http://ejournals.ncert.gov.in/index.php/SS/article/view/2486. Acesso em: 17 aug. 2025.