论文部分内容阅读
高中化学离子型推断题,因综合性强、思维容量大而备受选拔性试题命题者的青睐。复习时,教师充分研究命题规律,积极培育核心素养,显得尤为必要。我们曾推出了一堂“离子型推断题的分析”课例,现将其教学思路分享在此,希望对大家有所启示。一、离子型推断题的命题方向(一)侧重定性考查【例1】强酸性溶液X中可能含有Na~+、K~+、NH_4~+、Fe~(2+)、Al~(3+)、CO_3~(2-)、SO_3~(2-)、SO_4~(2-)、Cl~-中的若干种,某同学为了确认其成分,取溶液X进行
High school chemistry ion inferring questions, because of comprehensive, thinking capacity is large and highly selective test questions proponents of all ages. When reviewing, it is even more necessary for teachers to fully study the law of propositions and actively cultivate core literacy. We have launched a lesson entitled “Analysis of ion-based inference problems” lesson, now share their teaching ideas here, I hope we have some inspiration. First, the ion proposition proposition direction (A) focus on qualitative test 【Example 1】 Strong acid solution X may contain Na ~ +, K ~ +, NH4 ~ +, Fe2 +, Al3 + ), CO_3 ~ (2 -), SO_3 ~ (2 -), SO_4 ~ (2 -), Cl ~ -, some students in order to confirm the composition, take the solution X