What is the mass number of an element if its atom contains 10 protons, 10 electrons and 12 neutrons? by Sunday | May 13 | Chemistry WAEC | 0 comments A. 32 B. 22 C. 20 D. 10 Correct Answer: Option B B. 22 Users Also Read These:Uranium of atom number 92 and mass number 238 emits…An atom 17 protons, 17 electrons and 18 neutrons has…The nucleon number and the proton number of a…A particle that contains 9 protons, 10 neutrons and…A particle that contains 9 protons; 10 neutrons and…