Which statement is true about the atomic mass? a. it is never greater than the atomic number b. it always equal the atomic number c. it always lowers the atomic number d. it can be greater than the atomic number

d. it can be greater than the atomic number          

Explanation:

Atomic mass number can be defined as the sum of number of protons and number of neutrons present in the nucleus of an atom. On the other hand, atomic number is determined by the number of protons present in the nucleus of the atom. Thus, atomic mass number can be equal or greater than the atomic number but cannot be less than it. Hydrogen has 1 proton and 0 neutrons. So, atomic mass number and atomic number are equal. For rest, the atomic mass number is greater than the atomic number. Thus, option d is correct.