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Class 9 Science Chapter 3 Atoms and Molecules Quiz 3
Quizzes are an essential tool for mastering any subject and Class 9 Science Atoms and Molecules Quiz 3 is no exception. Atoms and Molecules quiz is designed to reinforce your understanding of key concepts from Chapter 3 Atoms and Molecules. It provides a practical way to test your knowledge, review important topics, and prepare for exams. By engaging in this Atoms and Molecules Test for Class 9 quiz 3, you can identify any gaps in your understanding and focus on improving those areas.
Covering a range of topics like atomic mass, molecular structure, and laws of chemical combinations, this Class 9 Chapter 3 Quiz ensures you’re thoroughly prepared. By revisiting concepts through Atoms and Molecules Practice Questions for Class 9, you sharpen your problem-solving skills, making complex ideas easier to recall during exams.
Remember to check out Quiz 1 and Quiz 2 from this chapter for a complete learning experience. These quizzes provide additional practice and ensure you’re well-prepared for the next step in your chemistry journey. Dive into this Atoms and Molecules Quiz 3 for Class 9 Science and take the next step toward mastering the chapter.
Rules of Class 9 Atoms and Molecules Quiz 3
- Time Limit: You have 15 minutes to complete the quiz, so make sure to keep track of your time and move through the questions efficiently.
- Multiple Choices: Each question comes with several answer options. Select the one that you believe is the most accurate based on your understanding of the topic.
- Single Correct Answer: Only one answer per question is correct, so choose carefully using your knowledge of the chapter.
- No Negative Marking: There’s no deduction for incorrect answers, so if you’re unsure, take an educated guess without worrying about penalties.
Structure of Class 9 Atoms and Molecules Quiz 3
- Total Questions: 10
- Topics Covered: This quiz covers the fundamental ideas from Chapter 3 Atoms and Molecules. You will encounter questions on atomic structure, laws of chemical combination, and the concept of molecules and molecular mass.
Best of luck! Trust your knowledge and use this quiz to reinforce your understanding of the chapter.
Class 9 Chemistry Chapter 3 Atoms and Molecules Quiz Questions
Question 1: Is it true that a positively charged ion is known as a Cation?
a) True
b) False
Answer:
The correct answer is a) True.
A positively charged ion is known as a cation. For example, in sodium chloride (NaCl), the sodium ion (Na⁺) is a cation.
Question 2: Is it true that magnesium sulphide is an ionic compound?
a) True
b) False
Answer:
The correct answer is a) True.
Magnesium sulphide is an ionic compound because it consists of magnesium and sulfur, where magnesium has a positive charge and sulfur has a negative charge.
Question 3: A molecule of oxygen is known as a diatomic molecule.
a) True
b) False
Answer:
The correct answer is a) True.
An oxygen molecule consists of two oxygen atoms, making it a diatomic molecule (O₂).
Question 4: For indivisible particles smallest in size, who coined the term “Parmanu”?
a) Leucippus
b) L. Lavoisier
c) Kanad
d) None
Answer:
The correct answer is c) Kanad.
Maharishi Kanad coined the term “Parmanu” to describe indivisible particles.
Question 5: These __________ aggregate in large numbers to form the matter.
a) Atoms
b) Photons
c) Bosons
d) Colloids
Answer:
The correct answer is a) Atoms.
Atoms aggregate in large numbers to form the matter that we can see, feel, or touch.
Question 6: What is not true about an atom?
a) Atoms are not able to exist independently
b) Molecular and ionic structures are formed by atoms
c) Atoms are always neutral in nature
d) Atoms aggregate in large numbers to form the matter that we can see, feel, or touch
Answer:
The correct answer is a) Atoms are not able to exist independently.
Atoms can exist independently, especially noble gases, which fulfill the octet rule and do not need to bond to be stable.
Question 7: Find the number of neutrons in silver having an atomic mass of 107.86.
a) 65
b) 71
c) 61
d) 47
Answer:
The correct answer is c) 61.
Silver has an atomic number of 47. To find the number of neutrons, subtract the atomic number from the atomic mass: 107.86 – 47 ≈ 61.
Question 8: Who was the first scientist who named the oxygen gas?
a) William Scheele
b) Priestley
c) Antoine Lavoisier
d) None
Answer:
The correct answer is c) Antoine Lavoisier.
Antoine Lavoisier named oxygen gas. He called it “oxygen” after discovering its role in combustion and respiration.
Question 9: The freezing point of mercury is:
a) 100K
b) 234.3K
c) 123.5K
d) 450K
Answer:
The correct answer is b) 234.3K.
The freezing point of mercury is -38.83°C, which converts to 234.3K.
Question 10: Identify the pair of substances having the same formula unit mass.
a) Calcium chloride, Potassium carbonate
b) Calcium oxide, Hydrochloric acid
c) Carbon monoxide, Ammonia
d) Carbon dioxide, Nitrous oxide
Answer:
The correct answer is d) Carbon dioxide, Nitrous oxide.
Carbon dioxide (CO₂) and nitrous oxide (N₂O) have the same formula unit mass.
Question 11: Sodium atom and sodium ion:
a) Are chemically the same
b) Have the same number of protons
c) Have the same number of electrons
d) React spontaneously with water
Answer:
The correct answer is b) Have the same number of protons.
Sodium atoms and sodium ions have the same number of protons (11), but sodium ions have one fewer electron than sodium atoms.
