Class 9 Science MCQ Questions of Atoms and Molecules with Answers. is ready as per the newest CBSE Syllabus and has answers to the questions provided here. This page has answers to 20 Multiple choice questions, that can assist you to understand the questions which will be asked within the examination.
MCQ Questions for class 9 Science with Answers had been prepared on the basis of recent exam pattern. We’ve Provided MCQ Questions with Answers to assist students to understand the concept all right.
Practice MCQ Questions for class 9 Chapter-Wise
1. Oxygen is –
(a) Monovalent
(b) Bivalent
(c) Trivalent
(d) Tetravalent
2. Neutron is
(a) Chargeless and Massless
(b) Chargeless and has Mass
(c) Has charge and Mass
(d) Has charge and Massless.
3. 3.42 g of sucrose are dissolved in 18g of water in a beaker. The number of oxygen atoms in the solution are
(a) 6.68 × 1023
(b) 6.09 × 1022
(c) 6.022 × 1023
(d) 6.022 × 1021
4. A change in the physical state can be brought about
(a) only when energy is given to the system
(b) only when energy is taken out from the system
(c) when energy is either given to or taken out from the system
(d) without any energy change
5. Mass of one atom of oxygen is
(a) 16/ 6.023 × 1023g
(b) 32/ 6.023 × 1023g
(c) 3/ 6.023 × 1023g
(d) 8u
6. Which of the following statements is not true about an atom?
(a) Atoms are not able to exist independently.
(b) Atoms are the basic units from which molecules and ions are
formed.
(c) Atoms are always neutral in nature.
(d) Atoms aggregate in large numbers to form the matter that we can see, feel or touch.
7. 1 u or 1 amu means
(a) 1/12th mass of C-12 atoms
(b) Mass of C-12 atom
(c) Mass of O-16 atom
(d) Mass of Hydrogen molecule
8. A sample of NH3 molecule irrespective of source contains 82.35% Nitrogen and 17.65% of Hydrogen by mass. This data supports:
(a) Law of Conservation of Mass
(b) Las of Multiple Proportions
(c) Law of Definite Proportions
(d) Avogadro’s Law
9. An element X is divalent and another element Y is tetravalent. The compound formed by these two elements will be:
(a) XY
(b) XY2
(c) X2Y
(d) XY4
10. The molecular formula of potassium nitrate is ________.
(a) KNO3
(b) KNO
(c) KNO2
(d) KON
11. Which of the following contains a maximum number of molecules?
(a) 1g CO2
(b) 1g N2
(c) 1g H2
(d) 1g CH4
12. Which of the following has maximum number of atoms?
(a) 18g of H2O
(b) 18g of O2
(c) 18g of CO2
(d) 18g of CH4
13. Which of the following would weigh the highest?
(a) 0.2 mole of sucrose (C12 H22 O11)
(b) 2 moles of CO2
(c) 2 moles of CaCO3
(d) 10 moles of H2O
14. The chemical symbol for sodium is
(a) So
(b) Sd
(c) NA
(d) Na
15. Which of the following statements is correct?
(a) Cathode rays travel in a straight line and have momentum.
(b) Cathode rays travel in a straight line and have no momentum
(c) Cathode rays do not travel in a straight line but have Momentum.
(d) Cathode rays do not travel in a straight line and have no momentum.
16. The maximum number of electrons in L shell is
(a) 8
(b) 18
(c) 28
(d) 38
17. Molecular mass is defined as the:
(a) Mass of one molecule of any substance compared with the mass of one atom of C – 12
(b) Mass of one atom compared with the mass of one atom of hydrogen
(c) Mass of one atom compared with the mass of one molecule
(d) None of the above
18. The chemical symbol for nitrogen gas is
(a) Ni
(b) N2
(c) N+
(d) N
19. Which of the following statements is not true about an atom?
(a) Atoms are not able to exist independently
(b) Atoms are the basic units from which molecules and ions are formed
(c) Atoms are always neutral in nature
(d) Atoms aggregate in large numbers to form the matter that we can see, feel or touch
20. A change in the physical state can be brought about
(a) only when energy is given to the system
(b) only when energy is taken out from the system
(c) When energy is either given to, or taken out from the system
(d) Without any energy change
