The most abundant isotope of hydrogen is :

The least abundant isotope of hydrogen is

The least abundant isotope of hydrogen is

The least abundant isotope of hydrogen is

The least abundant isotope of hydrogen is

The most abundant ore of Fe is

The most abundant and least abundant isotopes of Hydrogen respectively are

Name the most abundant compound of hydrogen present on earth.

The isotopes of hydrogen are :

Assertion(A) One atomic mass unit is defined as one twelth of the mass of one carbon-12 atom. Reason(R) Carbon-12 isotope is the most abundant isotope of carbon and has been chosen as standard.