HARD
9th CBSE
IMPORTANT
Earn 100

The nucleus of an atom contains 9 protons and 10 neutrons. Name this atom and calculate the following:
Atomic number 
Mass number 
Number of electrons

Important Questions on Structure of Atom

HARD
9th CBSE
IMPORTANT
Calculate the number of protons, neutrons and electrons in a species  O816. What is the atomic number and mass number of this species?
EASY
9th CBSE
IMPORTANT
Define an atomic orbit as proposed by Bohr. Write the symbols of the first three orbits of an atom.
EASY
9th CBSE
IMPORTANT
The gold foil used by Rutherford in the alpha-particle scattering experiment was 1000 atoms thick.
What does it mean?
EASY
9th CBSE
IMPORTANT
Draw the first three orbits of Bohr's atomic model.
 
HARD
9th CBSE
IMPORTANT

Composition of the nuclei of two species X and Y are given as follows:

Species  X Y
Protons 6 6
Neutrons 6 7

Give the mass numbers of X and Y. What is the relation between the two species?

MEDIUM
9th CBSE
IMPORTANT
Describe Rutherford's experiment of alpha-particle scattering. What were the main observations of this experiment?
 
HARD
9th CBSE
IMPORTANT
Write the main postulates of Bohr's atomic model. How do these postulates explain that the moving electron will not fall into the nucleus?
HARD
9th CBSE
IMPORTANT
Compare the atomic models you have studied in your book of class IX.