An isotope has an atomic number of 15 and a mass number of 31. The number of protons it contain is? by Sunday | Oct 10 | Chemistry JAMB | 0 comments A. 16 B. 15 C. 46 D. 31 Correct Answer: Option B – 15 Users Also Read These:One mole of a compound M(HCO3)2 has a mass of 162g.…What is the mass number of an element having 20…Chlorine consisting of two isotopes of mass number…Chlorine consisting of two isotope of mass number 35…Uranium of atom number 92 and mass number 238 emits…