Xam Idea Class 12 Pdf Free Download Chemistry

The Framework defines core ideas as central to the discipline, providing underlying support for a wide range of concepts across the discipline, and most importantly, as having explanatory and predictive power (NRC, 2012a). Core ideas provide students with the organizational structure that supports the acquisition of new knowledge to construct more expert-like knowledge structures. Expert knowledge is not simply a list of isolated facts or propositions that are relevant to their domains; instead, such knowledge is organized around core concepts or big ideas that allow experts to connect and use knowledge in new situations (NRC, 2000). Thus, centering introductory courses around core ideas rather than separated topics provides students with the opportunity to build a network of ideas that are connected and contextualized.

With this in mind, the Framework was adapted at the institution of interest in an effort to transform the introductory chemistry, biology, and physics courses. Faculty at the institution of interest identified the core ideas of gateway courses as part of transformation efforts (Table 1) that focus on what students are expected to learn in these courses at the introductory level and what they are expected to know going into upper-level courses (Laverty et al., 2016; see course descriptions in the Setting and Participants section).

Download 🔥 https://tlniurl.com/2y2Flm 🔥

The research presented here is guided by two research questions:What do students consider to be the big ideas of their introductory chemistry and biology courses along with the reasoning behind their perceptions?

The introductory biology course at the same institution (B1) mostly focuses on cell and molecular biology and enrolls about 2300 students per year, with 150 to 250 students per lecture section. Similar to the GC1/GC2 courses at this institution, B1 was undergoing a transformation with their curriculum inspired by the Vision and Change report (AAAS, 2011). As part of this transformation, B1 instructors were beginning to place emphasis on seven biology core ideas (chemical and physical basis of life, matter and energy, cellular basis of life, system, structure and function, information flow, exchange, and storage, evolution), which were identified by the faculty at the institution (Laverty et al., 2016). B1 students were presented with these seven core ideas at the beginning of the semester and were reminded of the applicable core ideas within context for each unit. This course used a commercially available textbook and associated online homework system (Mason et al., 2015); the lectures incorporated in-class activities and students participated in five modeling activities throughout the semester. In these modeling activities, students were asked to construct representations of a system and then predict and explain the biological processes involved.

Phases 2 and 3 from the interview guide (Figure 1) were modified to develop a survey (Figure 2) that was administered via Qualtrics at the end of the Spring 2016 semester to students enrolled in GC2. Out of the 815 students registered in the GC2 course, 109 students completed all four questions of interest on the perceived usefulness of the topics from their chemistry courses (GC1/GC2) and biology course (B1). Responses from these 109 students (70 self-identified as female and 39 as males) who had a course grade average of 3.18 (range from 0.0 to 4.0) were used for the data analysis. The students included in our analysis were representative of the students registered in the course (see Supplemental Material S.1 for student demographics).

The findings from research question 2 show that, when students were asked to make explicit connections between their chemistry and biology courses, they were able to identify productive common ideas. Generally, students identified an average of two or three overlapping ideas during the interviews and surveys, which means that these could be used by instructors to support and facilitate connection between disciplines. In general, students were more likely to indicate that chemistry ideas were useful in biology, rather than vice versa. This is not surprising, indeed the biology course has a prerequisite of at least one chemistry course, while the chemistry course has no biology prerequisite.

The findings presented in this paper highlight the importance of being explicit about not only introducing core ideas, but also emphasizing their connections to phenomena during instructional activities. Carefully introducing such ideas and providing students with assessments that support the development of connected and integrated ideas will enable students in developing more expert-like understanding of the discipline. Instructors should also provide explicit opportunities to support students in their understanding of core ideas. These ideas need to be introduced in a consistent manner and returned to as often as possible to help students strengthen connections between core ideas and topics.

Finally, our findings have implications for the order in which the chemistry and biology courses are taught. Our study highlights how students were able to identify a larger number of chemistry ideas that they found useful to support their understanding of biological phenomena, while it was much more difficult for them to identify biology ideas that would support their understanding in chemistry. Therefore, this study provides evidence that the order in which chemistry and biology courses are taken does have some impact on how students use knowledge from one course to apply toward another course. Here, the student responses indicate that chemistry courses being taught before biology may lend a better knowledge framework of understanding for their chemistry knowledge to be used and applied in their biology courses.

The results presented here were gathered at a single institution where both the chemistry and biology courses had either been transformed or were in the process of being transformed. Instructors in both courses valued and placed large emphasis on core ideas. Therefore, findings from a different time point of the transformation within the same institution, different institutions, or courses using a different curriculum might result in different findings from the ones presented here. In addition, students were not asked to provide a description and explanation for each of the topics/ideas listed during the interviews; therefore, future research would be warranted to further explore these ideas and gain a better understanding on how students are using the ideas listed. Furthermore, additional research is needed to understand why students listed individual ideas as being important for one discipline only but struggled to identify potential connections when asked to purposely think about how the two disciplines overlapped.

AACT strives to provide teachers of chemistry with the best teaching resources. Most of the Classroom Resource Library is made up of content from great teachers who created and shared their own work. Currently there are over 1000 classroom resources available in the library for K-12 teachers of chemistry to use in their classrooms. The library is organized into three grade bands (elementary, middle and high). High school resources that are appropriate for advanced classes, such as AP or IB chemistry, can be found in our AP Collection. A large collection of multimedia resources, including animations, simulations and videos are also available for use. Additionally, select resources are highlighted as part of themed resource collections. All of the available teaching resources are classified in the library by topic, subtopic, as well as resource type. We also have External Teaching Resources from the chemistry community.

Students have difficulty distinguishing between physical and chemical change, despite formal teaching, and the distinction is somewhat arbitrary. However an understanding of the differences between purely physical processes such as melting, evaporation and boiling and the changes that take place in chemical reactions, particularly the idea that new substances are formed, is important to an understanding of chemistry and students very frequently confuse the two. The following conversations are typical:

Research shows that students frequently use the term chemical change to describe changes in physical state. Freezing and boiling are considered to be examples of chemical reactions. This depends on their conception of substance. If students regard ice as a different substance from liquid water they are likely to classify the melting of ice as a chemical change. One study found that 80% of students considered a difference in colour between the reactant and product evidence of chemical change. Students can consider potassium permanganate (Condy's crystals) dissolving in water to be a chemical change because of the intense difference in colour. Melting and expansion on heating were also considered to be evidence of chemical change by some students.

When teaching about physical and chemical changes it is important to allow students to see the classification as a continuum. They should be able to observe a number of changes and formulate their views on the kind of change and problems with the classification process. Students should come to see that chemical reactions produce new chemicals distinct from the starting materials but that chemical processes can be reversed. Examining examples of reversible chemical reactions and considering why it is difficult to reverse many chemical changes can be very useful.

Promote reflection on and clarification of existing ideas

The following activities are intended to get students identifying and then refining their ideas about physical and chemical change. It is important for students to observe a number of changes and to record their opinions on what is happening. They could record this in a booklet where they write about and draw results and observations. They should be encouraged to formulate and record hypotheses about what is happening with the knowledge that their opinions will not be assessed at this stage. ff782bc1db