Page 2 - 3.HOME ASSIGNMENT-CONCEPT MAP

Q6 Electrons are the fundamental particles of all atoms and are ………….. 1
in all the elements.

Q7 Anode rays are deflected towards ……. plate and they are composed of 1
………… charged particles.

Concept: Thomson’s model of an atom & its drawbacks

Q1. Assertion: The magnitude of positive charge and negative charge in an 1
atom is equal.
Reason: Atoms are electrically neutral.
Q2 Assertion: Thomson’s model of an atom was based on protons. 1
Reason: The magnitude of positive and negative charges in an electron
are equal.
Q3 Assertion: Electrons carry negative charge. 1
Reason: Electrons were discovered by E. Goldstein
Q4 Thomson’s model of an atom is called: 1
(a) Planetary model.
(b) Plum pudding model.
(c) Nuclear model.
(d) None of the above.
Q5 The first model of an atom was proposed by: 1
(a) J.J. Thomson
(b) Neils Bohr
(c) E.Goldstein
(d) James Chadwick

Q6 The discovery of neutrons led to the proposal of Thomson’s model of an 1
atom. (T/F)

Concept: Rutherford’s alpha particle scattering experiment and
planetary model of an atom
Q1. Assertion: Most of the Alpha particles passed through the gold foil. 1
Reason: Alpha particles carry negative charge.
Q2 Assertion: Most of the Alpha particles were deflected. 1
Reason: An atom has a positively charged nucleus.
Q3 Assertion: Electrons do not lose energy during their rotation. 1
Reason: Electrons carry negative charge.
Q4 Alpha particles are composed of: 1

(a) Doubly charged Calcium nucleus.
(b) Doubly charged Hydrogen nucleus.
(c) Doubly charged Hydrogen nucleus.
(d) Doubly charged Helium nucleus.

Q5 Which of the following was not true about Rutherford’s alpha particles 1
scattering experiment?

(a) Most of the alpha particles passed through the gold foil.
(b) Alpha particles are positively charged.