An isotope has an atomic number of 15 and a mass number of 31. The number of proton it contains is? by Sunday | Sep 16 | Chemistry JAMB | 0 comments A. 16 B. 15 C. 31 D. 46 Correct Answer: Option B – 15 Users Also Read These:The nucleon number and the proton number of a…An element having the atomic number 17 will resemble…The nucleon number and the proton number of a…The atomic number of an isotope of hydrogen is equal…Chlorine consisting of two isotope of mass number 35…