This book has been published by National Book Foundation
CHEMISTRY GRADE – 9 is developed according to the National Curriculum 2006 and National Style Guide. It is being published since 2012 and in 2015 it was presented under the new management and supervision of textbook development principles and guidelines with a new design and layout.
Chemistry is one of the most exciting and useful subjects. It may not be an easy subject for you. If you develop a sound approach to thinking through an idea and solving a problem, you will find it easy. This textbook provides several ways to develop this approach.
This textbook has been made friendly by giving problem-solving strategies. This strategy is to facilitate reasoning, not memorizing toward a solution. With each skill or concept, self-assessment exercises have been given. These exercises would encourage students to think, develop skills, and use the information for a variety of purposes.
It is caused by the development of skills such as questioning, observing, inferring, and predicting, measuring, hypothesizing, classifying, designing experiments, collecting data, analyzing data, and interpreting data. At the end of each chapter summary of the key points is given. This provides quick reviews of the salient features of each chapter.
Science, Technology, and Society connections have also been given in each chapter. These will help to understand the impact of science and technology on society. Students will learn how scientists decide what constitutes scientific knowledge, how science is related to other ways of knowing, and how people have contributed to and influenced developments in science.
This textbook has been developed according to Student-Centered Inquiry-Based (SCIB) criteria. It will encourage students to develop skills and think scientifically rather than simply memorize and study scientific facts. It is also expected from teachers that they will engage students in scientific inquiry activities to develop such skills.
Our efforts are to make textbooks teachable with quality, i.e. maintaining standards. It is a continuous effort and we will get feedback on the yearly feasibility reports and redesign the textbook every year. The test items given in the exercises are for learning reinforcement. The examination questions should be prepared according to the SLO’s and Bloom’s Taxonomy.
Quality of Standards, Pedagogical Outcomes, Taxonomy Access, and Actualization of Style is our motto. With these elaborations, this series of new development was presented for use. After educational feedback, research, NCC Standards 2016, the book is being published again.
Chapter 1 FUNDAMENTALS OF CHEMISTRY
After completing this lesson, you will be able to: • Change atomic mass, molecular mass and formula mass into gram atomic mass, gram molecular mass and gram formula mass. • Differentiate between branches of chemistry. • Differentiate between empirical and molecular formula. • Differentiate among elements, compounds and mixtures. • Differentiate between molecules and molecular ions • Define ions, molecular ions, formula units and free radicals. • Define atomic number, atomic mass, atomic mass unit. • Define relative atomic mass based on C-12 scale. • Distinguish between atoms and ions. • Distinguish between ion and free radical. Classify the chemical species from given examples. • Distinguish between matter and a substance. • Describe how Avogadro’s number is related to a mole of any substance. Distinguish among the terms gram atomic mass, gram molecular mass and gram formula mass. • Identify the representative particles of elements and compounds. • Identify and provide example of different branches of chemistry. • Relate gram atomic mass, gram molecular mass and National gram formula mass to mole.
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