Q.1.
The lightest chemical elements include _______.
Q.2.
The periodic table only contains _________.
Q.3.
The means by which all chemical elements are organized based on their atomic number, electron configurations and their recurring chemical properties is called the _________.
Q.4.
Of the confirmed elements ____ occur naturally.
Q.5.
This is the distribution of electrons found in an atom or molecule.
Q.6.
The rows found in the periodic table are referred to as _____.
Q.7.
What are the four common elements?
Q.8.
The number of protons in the nucleus of an atom is known as the _______.
Q.9.
He has been credited with publication of the periodic table in 1869.
Q.10.
The columns found in the periodic table are known as ______.