NCERT Class-9 Science Solutions: Chapter 4-Structure Of The Atom Part 1

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Multiple Choice Questions

Question 1:

Which of the following correctly represent the electronic distribution in the atom?

Answer: B

Image of electronic distribution in the Mg atom

Image of Electronic Distribution in the Mg Atom

Image of electronic distribution in the Mg atom

Question 2:

Rutherford’s ‘alpha particles scattering experiment’ resulted in to discovery of

  1. Electron

  2. Proton

  3. Nucleus in the atom

  4. Atomic mass

Answer: C

Question 3:

The number of electrons in an element and the number of neutrons is 16. Which of the following is the correct representation of the element?

Answer: A

Question 4:

Dalton’s atomic theory successfully explained

  1. Law of conservation of mass

  2. Law of constant composition

  3. Law of radioactivity

  4. Law of multiple proportion

  5. (i), (ii) and (iii)

  6. (i), (iii) and (iv)

  7. (ii), (iii) and (iv)

  8. (i), (ii) and (iv)

Answer: D

Image of Dalton's Atomic Theory

Image of Dalton's Atomic Theory

Image of Dalton's Atomic Theory

Question 5:

Which of the following statements about Rutherford’s model of atom are correct?

  1. Considered the nucleus as positively charged

  2. Established that the α–particles are four times as heavy as a hydrogen atom

  3. Can be compared to solar system

  4. Was in agreement with Thomson’s model

  5. (i) and (iii)

  6. (ii) and (iii)

  7. (i) and (iv)

  8. only (i)

Answer: A

Question 6:

Which of the following are true for an element?

  1. (i) and (ii)

  2. (i) and (iii)

  3. (ii) and (iii)

  4. (ii) and (iv)

Answer: D