An element and its isotope only differ in the number of? by Sunday | Nov 3 | Physics JAMB | 0 comments A. protons B. electrons C. ions D. neutrons Correct Answer: Option D – neutrons Users Also Read These:An element of nucleon number P and atomic number Q…If the relative molecular mass of an element is not…The nucleon number and the proton number of a…Chlorine consisting of two isotope of mass number 35…The atomic number of an isotope of hydrogen is equal…