Question

Write True or False. Correct the false statements.
a) Most of the properties of elements and their components depend on their mass
number.
b)The Valency of 17Cl is 7.
c)Total number of electrons found in L shell will be 8.
d) Isotopes of an element have same chemical properties.
e) Electrons reduce the repulsive force between positively charged protons.
f)The stability of the nucleus is determined by the Neutron – Proton ratio.
g) When an electron returns from higher energy level to lower energy level, it absorbs
energy.
h) Smaller the size of the orbit, smaller is the energy of the orbit.
i) Neils Bohr’s atomic model does not explain the stability of atom.
j) Bohr’s theory became the basis of modern physics known as Quantum Mechanics.

TNSCERT Class 9 General Science Ch4 Atomic Structure

Answer 1

1. true 2 . false 3.t 4.f 5.t 6.t 7.f 8.f 9.t 10.t

Answer 2

Answer and explanation:

a) Statement is false.  

The true statement is that most of the properties of elements and their components depend on number of valence shell electron.

b) Statement is false.  

It is because the valency of 17Cl is 1. The electronic configuration of chlorine is 2, 8, and 7. The standard formula to find the valency is:

Valency = 8 – valence electron

Therefore valency of chlorine is 8 – 7 = 1

c) Statement is true.

d) Statement is true.

e) Statement is true.  

f) Statement is true.

g) Statement is false.

During the given process energy is released and not absorbed.

h) Statement is true.

i) Statement is false.

It gives detail explain about atoms stability.

j) Statement is false.

Erwin Schrödinger model became the basis of modern physics known as Quantum Mechanics.