MEDIUM
9th CBSE
IMPORTANT
Earn 100

Identify the isotopic pair(s) out of the following species?
C816,C146,N14,O18,N16787

Important Questions on Structure of the Atom

EASY
9th CBSE
IMPORTANT
Name the isotope used as a fuel in nuclear reactors.
EASY
9th CBSE
IMPORTANT
What is the number of subatomic particles in U-235 isotope?
EASY
9th CBSE
IMPORTANT
The cathode ray experiment was done for the first time by
EASY
9th CBSE
IMPORTANT
How many neutrons are present in the nucleus of a hydrogen atom?
EASY
9th CBSE
IMPORTANT
Which of the following correctly represent the electronic distribution in the Mg atom?
EASY
9th CBSE
IMPORTANT
Number of electrons present in N3- ion is
MEDIUM
9th CBSE
IMPORTANT

The number of electrons in an element X is 15 and the number of neutrons is 16. Which of the following is the correct representation of the element?

MEDIUM
9th CBSE
IMPORTANT
In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R).
Assertion: The valency of an atom of fluorine is 7.
Reason: The number of electrons present in the outermost shell of an atom is known as the valence electrons.
Mark the correct choice as: