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When judging what a circle is, almost 100% of people can answer correctly, but what is a circle? More than 98% of people can't answer: a circle is a two-dimensional space, closed in shape, and each point on the line is the same distance from the center of the circle.
There are a lot like that. If you ask yourself, most of the specific knowledge and numeracy skills of the examples learned in middle school that have nothing to do with work have been forgotten, and only basic common sense and thinking methods remain in our minds. This raises a question for the teaching of chemistry in secondary schools:
What should we teach our students?
Any concept of education is a product of the times. Education is closely related to society, in today's world, the society is constantly developing and changing, and our concept of teacher education must be changed. In today's rapid development of knowledge, lifelong learning has become inevitable, the school is no longer the only place for knowledge learning, the last place, the content of the knowledge imparted by teachers in the classroom itself has become less important, "teaching people to fish, it is better to teach people to fish", it is important to teach students the ability to acquire, process and use knowledge, especially the ability to innovate.
In order to develop students' abilities, teachers must step beyond the original role of knowledge transmitters. Of course, it is still the responsibility of teachers to pass on knowledge, but this should not be regarded as the whole of teachers' work, let alone the ultimate goal. There should be a change in teaching thinking, and teaching should be changed from teacher-centered teaching to teacher-led and student-centered.
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When the reaction reaches equilibrium with t = 4 min, it can be seen in the figure that the initial concentration of CO is c(CO) = moll
When equilibrium is reached.
mol l according to the noise formula: mold pin v
c at the beginning - c at the end) to ascend the code d
moll *min
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The significance of the first lesson of the first year of high school is extraordinary, it is the most important lesson for the teacher's position in the minds of the students, as the saying goes"A good start is half the battle"。According to the requirements of the syllabus, senior one chemistry is to review the junior high school chemistry knowledge for nine consecutive class hours, and it is very necessary to listen carefully and review the transition between junior high and high school. The reasons are:
Chemistry in junior high school emphasizes qualitative analysis and only requires memorization of phenomena or conclusions, while in high school, it is necessary to combine qualitative and quantitative, and it is clear that high school is not only memorized"What it is"In addition, it is also required to find out"Why"with"What it is"with"How much"Junior high school chemistry is mainly based on visual thinking, usually starting from familiar, specific and intuitive natural phenomena or demonstration experiments to establish chemical concepts and laws. In addition to strengthening visual thinking, high school chemistry also establishes chemical concepts and laws through abstract and idealized models.
In junior high school, there is a lot of knowledge that is memorized to a large extent, and many students' learning methods are rote memorization, learning depends on teachers, lacks independent thinking ability, does not summarize and summarizes the knowledge points learned, and develops the habit of passively accepting knowledge; In high school, students are required to have a strong comprehension, memorize after understanding, and be able to improve the knowledge they have learned, learn to bypass others, draw inferences from one another, and deeply understand the principles of chemistry. If you still use rote memorization to learn high school chemistry, you will get twice the result with half the effort. Therefore, teachers will use the review time to instill high school chemistry learning ideas and learning methods.
In addition to gradually adapting to the learning requirements of high school chemistry, new students also need to adapt to the teaching methods of high school teachers and the learning methods of high school chemistry. Different from the teaching method of junior high school, the teaching process of high school is characterized by large capacity, fast progress, many knowledge points, and strong comprehensiveness. The requirements of high school teachers are also different from those of junior high school, and they focus on the point-and-click of methods"Slightly contempt"Repeat it many times over and over again.
Use the pre-school review time to make students adapt to the new requirements, accept the teacher's teaching style and adapt to the teacher's teaching habits, and establish a good teacher-student relationship.
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Chemistry is a very important subject, not only because it is a key subject in the college entrance examination, but also because of the great role of chemistry in promoting human life. Junior high school chemistry is relatively basic, and the connection with high school chemistry is relatively weak, which also makes it difficult to carry out senior one chemistry.
Therefore, how to grasp the critical period of high school freshman and improve the interest and efficiency of chemistry learning of freshmen has become the key to high school chemistry teaching. Based on this, this paper is here to do a good job in the teaching of chemistry for freshmen, in order to provide useful reference for relevant people and promote the development and progress of high school chemistry teaching.
1. Consolidate the review and do a good job of cohesion.
Fundamentally, the main reason for the low quality of chemistry teaching in senior one is the poor connection between junior and senior high school chemistry teaching. On the one hand, the content of junior high school chemistry is relatively basic, and the theory of knowledge is not too abstract, so the learning difficulty of students is low, while the knowledge of high school chemistry is relatively profound, which leads to the sharp increase of students' learning difficulty. On the other hand, high school chemistry teachers often underestimate the ability of students, especially those who have been engaged in senior high school chemistry teaching for a long time, and their ability prediction of freshmen is wrong, which makes it difficult to achieve good results in chemistry teaching.
Therefore, in order to do a good job in the teaching of chemistry for freshmen, teachers should first consolidate students' junior high school chemistry knowledge, not only for the knowledge theory of junior high school chemistry, but also to guide students to develop effective chemical thinking, learning methods and learning skills.
On this basis, senior chemistry teachers should do a good job of bridging the work, and fully grasp the knowledge base and their own abilities of senior freshmen. Based on this, senior chemistry teachers can break the shackles of teaching materials, carry out teaching according to students' real abilities, and improve the quality and efficiency of teaching.
2. Use life-based situational teaching to quickly enter the new curriculum.
Chemistry teachers should make full use of life-based teaching to quickly enter the formal curriculum, so that students can quickly adapt to the learning environment and chemistry courses in the first year of high school, quickly find their own roles, and achieve real improvement in active teaching activities.
For example, in the section "Redox Reactions", teachers can guide students to think about redox reactions in their daily lives, such as metal rusting, flour fermentation, and so on. Teachers can let students feel the redox reaction through real-life cases and feel the reality of chemistry.
In general, the chemistry of senior one and junior high school has been greatly improved, which has increased the difficulty of learning, and the students' psychology is not adaptable. Therefore, teachers need to combine the actual situation of high school freshmen, grasp their characteristics to carry out teaching, and improve the quality and efficiency of teaching.
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