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:if an element X with atomic number 13 combines with…An isotope has an atomic number of 15 and a mass…Uranium of atom number 92 and mass number 238 emits…When a nucleus is formed by bringing protons and…What is the mass number of an element having 20…