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3. Atoms and Molecules Science class 9 in English Medium ncert book solutions Additional -Questions
3. Atoms and Molecules Additional -Questions – Complete NCERT Book Solutions for Class 9 Science (English Medium). Get all chapter explanations, extra questions, solved examples and additional practice questions for 3. Atoms and Molecules Additional -Questions to help you master concepts and score higher.
3. Atoms and Molecules Science class 9 in English Medium ncert book solutions Additional -Questions
NCERT Solutions for Class 9 Science play an important role in helping students understand the concepts of the chapter 3. Atoms and Molecules clearly. This chapter includes the topic Additional -Questions, which is essential from both academic and examination point of view. The solutions provided here are prepared strictly according to the latest NCERT syllabus and follow the guidelines of CBSE to ensure accuracy and relevance. Each question is explained in a simple and student-friendly manner so that learners can grasp the concepts without confusion. These NCERT Solutions are useful for regular study, homework help, and exam preparation. All textbook questions are solved step by step to improve problem-solving skills and conceptual clarity. Students of Class 9 studying Science can use these solutions to revise important topics, understand difficult questions, and practise effectively before examinations. The chapter 3. Atoms and Molecules is explained in a structured way, making it easier for students to connect the theory with the topic Additional -Questions. By studying these updated NCERT Solutions for Class 9 Science, students can build a strong foundation, boost their confidence, and score better marks in school and board exams.
3. Atoms and Molecules
Additional -Questions
Chapter– 3 ATOMS AND MOLECULES
Additional And Important Questions with Solution:
Ques.1 – Who had found two important laws of chemical combination.
Ans. - Antoine L. Lavoisier .
Ques.2 – Write the name of two important laws of chemical combination which is found by Antoine L. Lavoisier.
Ans. – (i) Law of conservation of mass. (ii) Law of constant proportions.
Ques.3 – Write the law of conservation of mass.
Ans. - Mass can neither be created nor destroyed in a chemical reaction.
Ques.4 – Write the law of constant proportions.
Ans. - In a chemical substance the elements are always present in definite proportions by mass.
Ques.5 – Define atoms according to Dalton atomic theory.
Ans. – All matter, whether an element, a compound or a mixture is composed of small particles called atoms.
Ques.6 – Write the Dalton’s atomic theory.
Ans. – Dalton’s atomic theory as follow.
(i) All matter is made of very tiny particles called atoms.
(ii) Atoms are indivisible particles, which cannot be created or destroyed in a chemical reaction.
(iii) Atoms of a given element are identical in mass and chemical properties.
(iv) Atoms of different elements have different masses and chemical properties.
(v) Atoms combine in the ratio of small whole numbers to form compounds.
(vi) The relative number and kinds of atoms are constant in a given compound.
Ques.7 - Which postulate of Dalton’s atomic theory is the result of the law of conservation of mass?
Ans. – The second postulate of Dalton’s atomic theory is the result of the law of conservation of mass.
Ques.8 - Which postulate of Dalton’s atomic theory can explain the law of definite proportions?
Ans. – The forth postulate of Dalton’s atomic theory can explain the law of definite proportions.
Ques.9 – Define atomic mass.
Ans. – The sum of numbers of protons and neutrons presence in a nucleus of an atom is known as atomic mass.
Ques.10 – Define atomic number.
Ans. – The number of protons presence in a nucleus of an atom is known as atomic number.
Ques.11 – What is ion?
Ans. – The charged atom is known as ion.
Example – Na +, Mg+, Cl-.
Ques.12 – Write the differences between atom and ion.
Ans –
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Atom |
Ions |
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See other sub-topics of this chapter:
1. Chapter Review 2. Text-book Questions 3. Additional -Questions 4. Additional -Questions 2 5. Additional -Questions 3