NCERT Class-9 Science Solutions: Chapter 3-Atoms And Molecules Part 1

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Multiple Choice Questions

Question 1:

Which of the following correctly represents of water?

  1. (i)

  2. (i) and (iv)

  3. (ii) and (iii)

  4. (ii) and (iv)

Answer: D

(ii)

water, because mass of of water is the same as its molar mass, i.e.,

(iv)

Question 2:

Which of the following statements is not true about an atom?

  1. Atoms are not able to exist independently

  2. Atoms are the basic units from which molecules and ions are formed

  3. Atoms are always neutral in nature

  4. Atoms aggregate in large numbers to form the matter that we can see, feel or touch

Answer: A

Inert gases exist in monoatomic form.

Question 3:

The chemical symbol for nitrogen gas is

Answer: B

Image of nitrogen

Image of Nitrogen

Image of nitrogen

Question 4:

The chemical symbol for sodium is

Answer: D

Image of sodium

Image of Sodium

Image of sodium

Question 5:

Which of the following would weigh the highest?

Answer: C

Weight of a sample in gram = number of moles × molar mass