MCQ Questions for Class 9 Science Chapter 3 Atoms and Molecules with Answers , कक्षा 9 विज्ञान अध्याय 3 परमाणु और अणु|SHM PATHSHALA

 MCQ Questions for Class 9 Science Chapter 3 Atoms and Molecules with Answers , कक्षा 9 विज्ञान अध्याय 3 परमाणु और अणु

1. The chemical symbol for nitrogen gas is 

A) N2

B) N

C) Ni

D) N+

ANSWER: (A) N2

1. Hydrogen (H)
2. Helium (He)
3. Lithium (Li)
4. Beryllium (Be)
5. Boron (B)
6. Carbon (C)
7. Nitrogen (N)
8. Oxygen (O)
9. Fluorine (F)
10. Neon (Ne)
11. Sodium (Na)
12. Magnesium (Mg)
13. Aluminum (Al)
14. Silicon (Si)
15. Phosphorus (P)
16. Sulfur (S)
17. Chlorine (Cl)
18. Argon (Ar)
19. Potassium (K)
20. Calcium (Ca)

 

2. Which of the following would weigh the highest? :

A) 0.2 mole of sucrose (C12H22O11)

B) 2 moles of CO2

C) 2 moles of CaCO3

D) 10 moles of H2O

ANSWER: (C) 2 moles of CaCO3

 

3.According to the law of definite proportions, ________. :

A) matter remains constant

B) matter can neither be created nor destroyed matter remains constant

C) a chemical compound is always made up of the same element combined together in the same fixed proportion matter remains constantconstant

D) All of these

ANSWER: (C) a chemical compound is always made up of the same element combined together in the same fixed proportion matter remains